IN- 


STATE OF  ILLINOIS 

DEPARTMENT  OF  REGISTRATION  AND  EDUCATION 
DIVISION  OF  THE 
STATE  GEOLOGICAL  SURVEY 

FRANK  W.  DE  WOLF,  Chief 


EXTRACT  FROM  BULLETIN  No.  33 


FURTHER  INVESTIGATIONS  OF  ILLINOIS 
FIRE  CLAYS 

BY 

C.  W.  PARMELEE  AND  C.  R.  SCHROYER 


Technology  and  tests  by  C.  W.  Parmelee 
Geology  by  C.  R.  Schroyer 


PRINTED  BY  AUTHORITY  OF  THE  STATE  OF  ILLINOIS 


URBANA,  ILLINOIS 
1921 


STATE  OF  ILLINOIS 


DEPARTMENT  OF  REGISTRATION  AND  EDUCATION 
DIVISION  OF  THE 
STATE  GEOLOGICAL  SURVEY 

FRANK  W.  DE  WOLF,  Chief 


EXTRACT  FROM  BULLETIN  No.  38 


FURTHER  INVESTIGATIONS  OF  ILLINOIS 
FIRE  CLAYS 

BY 

C.  W.  PARMELEE  AND  C.  R.  SCHROYER 


Technology  and  tests  by  C.  W.  Parmelee 
Geology  by  C.  R.  Schroyer 


PRINTED  BY  AUTHORITY  OF  THE  STATE  OF  ILLINOIS 


URBANA,  ILLINOIS 
1921 


Digitized  by  the  Internet  Archive 
in  2017  with  funding  from 

University  of  Illinois  Urbana-Champaign  Alternates 


https://archive.org/details/furtherinvestigaOOparm 


5'5'J,  £ I 


«? 

r* 


STATE  OF  ILLINOIS 

DEPARTMENT  OF  REGISTRATION  AND  EDUCATION 

DIVISION  OF  THE 

STATE  GEOLOGICAL  SURVEY 

FRANK  W.  DeWOLF,  Chief 


Committee  of  the  Board  of  Natural  Resources 
and  Conservation 


W.  H.  H.  Miller,  Chairman 

Director  of  Registration  and  Education 

Kendrick  C.  Babcock 

Representing  the  President  of  the 
University  of  Illinois 


Rollin  D.  Salisbury 
Geologist 


Fig.  43.  Index  map  showing  the  locations  of  clay  samples  and  the  approximate  position  of 

the  outcrop  of  the  Cheltenham  clay. 


FURTHER  INVESTIGATIONS  OF  ILLINOIS 
FIRE  CLAYS 

By  C.  W.  Parmelee  and  C.  R.  Schroyer 


OUTLINE 

TAGE 

Foreword  8 

Introduction:  A general  discussion  of  clays 9 

The  classification  of  clays 9 

Purpose  and  difficulties  9 

A proposed  classification  10 

Types  and  uses  of  clays 12 

Kaolin  and  china  clay 12 

Secondary  kaolins  12 

Ball  clay  13 

Refractory  clays  13 

Plastic  refractory  bond  clays 15 

Architectural  terra  cotta  clays 16 

Stoneware  clays  17 

Sagger  clays  : 17 

Sanitary  ware  clays  18 

Paving  brick  clays 18 

Face  brick  clays  18 

Conservation  of  clays 19 

The  physical  properties  and  the  methods  of  testing  the  clays 19 

Preliminary  preparation  21 

The  test  pieces  21 

Formation  21 

Drying  22 

Raw  clays:  their  properties  and  the  methods  of  testing 22 

Shrinkage  22 

Linear  22 

Volume  22 

Water  of  plasticity  23 

Shrinkage  water  23 

Pore  water  23 

Fineness  24 

Slaking  24 

Transverse  strength  25 

Bonding  strength  25 

Burned  clays:  their  properties  and  methods  of  testing 26 

* Pyrometric  methods  used  26 

Burning  shrinkage  29 

Porosity  29 

Fusion,  or  deformation  tests  29 

Distribution  of  Illinois  clays  30 


5 


PAGE 

Clays  of  the  embay ment  area  31 

Paleozoic  floor  and  border 31 

Correlation  and  division  of  the  embayment  deposits 31 

Cretaceous  system  35 

Upper  Cretaceous  series  35 

Ripley  formation  35 

Lithologic  character  35 

Tertiary  system  36 

Eocene  series 36 

Midway  formation 36 

Lithologic  character  37 

Wilcox  group  38 

Pliocene  series  39 

Quaternary  system  40 

Pleistocene  series  40 

Loess  40 

Recent  series  40 

Alluvial  deposits  40 

Elevation  of  the  Illinois  embayment  clays 41 

Field  and  laboratory  notes  on  the  embayment  clays 42 

Union  County,  Mountain  Glen  area 42 

Pits  of  the  Illinois  Kaolin  Company 42 

Pits  of  the  French  Clay  Blending  Company 45 

Goodman  pit  45 

Location  and  methods  of  working 45 

Geology  46 

Mines  of  Frederick  E.  Bausch 48 

Location  and  method  of  working 48 

Geology  48 

Elmer  Gant  mine 48 

T.  P.  Sifford  pit 49 

Maddox  and  Nixon  pits.., 49 

Smaller  pits  49 

Comparison  with  the  clays  near  Mayfield,  Kentucky 51 

Comparison  with  the  clays  of  Lutesville,  Missouri 51 

Results  of  tests  52 

Massac  County  64 

Paducah  Pottery  Company’s  pit 64 

Clays  from  the  vicinity  of  Round  Knob 64 

Clay  from  the  Obermark  property 65 

Results  of  tests  65 

Pulaski  County  67 

Clays  from  the  vicinity  of  Grand  Chain 67 

Clay  from  the  vicinity  of  Caledonia 68 

Results  of  tests  68 

Alexander  County  74 

Clays  from  the  Aetna  Powder  Company’s  land 74 

Results  of  tests  s • • • • 74 

Clays  of  Pennsylvanian  age 76 

Field  and  laboratory  notes  on  Pennsylvanian  clays 76 

Monroe  County 76 

Results  of  tests 76 

Madison  County  78 

Results  of  tests  78 


6 


PAGE 

Calhoun  County  80 

Results  of  tests  81 

Greene  County  82 

Results  of  tests  84 

Scott  County  94 

Results  of  tests  . : 96 

Pike  County  98 

Results  of  tests  99 

Adams  County  102 

Brown  County  102 

Schuyler  County  102 

McDonough  County  102 

Results  of  tests  105 

Fulton  County  112 

Results  of  tests  112 

Mercer  County  113 

Results  of  tests  113 

Rock  Island  County. 115 

Results  of  tests  115 

La  Salle  County  118 

Results  of  tests  125 

Grundy  County  141 

Results  of  tests  142 

Johnson  County  145 

Results  of  tests 146 

Tabulation  of  certain  physical  tests .. 146 

Summary:  Grouping  of  clays  according  to  uses 149 

ILLUSTRATIONS 

FIGURE  PAGE 

43.  Index  map  showing  the  location  from  which  clay  samples  were  taken  and 

the  approximate  position  of  the  Cheltenham  clay  horizon 4 

44.  Hand  plunger  machine  for  molding  briquets 20 

45.  Apparatus  for  saturating  briquets  in  vacuo 28 

46.  Map  showing  the  outcrop  of  the  embayment  deposits  in  Illinois  with  their 

relations  to  similar  deposits  farther  south 32 

47.  Diagrammatic  sketches  of  the  “K”  pit  of  the  Illinois  Kaolin  Company 43 

48.  View  of  the  southwest  wall  of  the  “K”  pit  of  the  Illinois  Kaolin  Company. . 44 

49.  View  of  Dr.  Goodman’s  mine  in  the  NW.  sec.  2,  T.  12  S.,  R.  2 W 46 

50.  Sketch  made  at  the  mouth  of  the  Goodman  shaft 47 

51.  Map  of  the  Mountain  Glen  area.  The  lands  known  to  include  deposits  of 

clay  having  proven  or  probable  commercial  value  are  indicated  by  shading.  50 

52.  Sketch  showing  the  clay  body  and  its  relations  to  the  surrounding  strata  at 

the  Paducah  Pottery  Company’s  clay  pit  north  of  Choat 64 

53.  Abandoned  fire  clay  pit  at  Golden  Eagle 81 

54.  View  of  the  Colchester  Brick  and  Tile  Company’s  pit  half  a mile  north  of  Col- 

chester, showing  No.  2 coal  near  the  top  and  stoneware  clay  at  the  base..  104 

55.  View  of  the  Utica  Firebrick  and  Clay  Company’s  pit  south  of  Utica;  No. 

2 coal  overlies  the  clay 119 

56.  View  of  the  clay  pit  at  the  west  end  of  the  Goose  Lake  area  in  Grundy 

County  142 

TABLE 

1.  Subdivisions  of  the  embayment  deposits 34 

7 


8 


ILLINOIS  FIRE  CLAYS 


FOREWORD 

Very  early  during  the  participation  of  the  United  States  in  the  World 
War,  the  importance  of  a better  knowledge  of  the  extent  and  character  of 
the  refractory  clay  resources  of  Illinois  was  recognized.  The  cessation  of 
importations  of  certain  types  of  such  clays  which  had  previously  been 
brought  from  enemy  countries  had  made  it  imperative  that  domestic  clays 
of  suitable  sorts  should  be  discovered,  if  possible.  Further,  the  general 
disturbance  of  the  economic  life  by  the  war  had  greatly  increased  the  costs 
and  difficulties  of  transportation  and  emphasized  the  necessity  for  a more 
comprehensive  survey  of  these  clays  than  had  yet  been  undertaken  by  the 
State. 

Consequently,  Mr.  C.  R.  Schroyer  of  the  Survey  was  assigned  the  duty 
of  visiting  deposits,  gathering  the  samples,  and  making  the  necessary  studies 
of  the  geological  conditions.  Prof.  Cullen  W.  Parmelee  of  the  Department 
of  Ceramic  Engineering  of  the  University  of  Illinois  was  given  charge  of  the 
testing  of  the  clays  which  was  done  in  the  laboratories  of  the  department 
mentioned. 

All  known  clay  deposits  which  gave  promise  of  being  of  refractory 
value  were  examined  and  areas  which  had  not  been  previously  investigated 
were  carefully  searched.  Fig.  43  shows  the  locations  of  all  deposits  sampled. 

The  work  was  well  advanced  when  the  armistice  was  signed,  but  the 
cessation  of  hostilities  was  not  considered  a justification  for  termination  of 
the  investigation  since  it  was  recognized  that  the  results  would  have  very 
considerable  permanent  economic  value.  Therefore,  the  work  has  been 
somewhat  extended  and  a few  clays  of  a non-refractory  type  have  been 
included  since  the  samples  were  already  at  hand. 

Since  the  clays  of  the  embayment  area  in  the  southern  counties  of  the 
state  have  proved  to  be  of  unusual  interest,  it  was  thought  desirable  to 
study  their  relation  to  the  very  important  deposits  of  the  embayment  area 
in  western  Tennessee  and  Kentucky.  The  authors  of  the  bulletin,  together 
with  Dr.  H.  Ries  of  the  U.  S.  Geological  Survey,  visited  the  deposits  of 
western  Kentucky  and,  accompanied  by  Mr.  Wilbur  A.  Nelson,  State  Geolo- 
gist of  Tennessee,  visited  those  of  the  latter  state. 

A visit  was  also  made  to  the  deposits  at  Lutesville  and  Glen  Allen,  Mis- 
souri, in  order  to  determine  what  relation,  if  any,  existed  between  that  area 
and  clay  deposits  in  the  southern  part  of  the  state. 

The  authors  therefore  wish  to  express  their  appreciation  of  the  assist- 
ance extended  to  them  by  the  gentlemen  named,  as  well  as  the  many  citizens 
of  this  State  who  have  contributed  in  various  ways  to  the  successful  prosecu- 
tion of  this  work. 


CLASSIFICATION  OF  CLAYS 


9 


INTRODUCTION:  A GENERAL  DISCUSSION  OF  CLAYS 

By  C.  W.  Parmelee 

The  Classification  of  Clays 

PURPOSE  AND  DIFFICULTIES 

It  is  possible  to  classify  clays  in  many  ways ; as  for  example,  mode  of 
origin,  mineralogical  character,  physical  properties,  and  uses,  and  several 
such  classifications1  have  been  published.  The  classification  here  presented 
is  an  attempt  to  correlate  certain  physical  properties  with  uses. 

Difficulties  are  experienced  in  such  an  attempt  because  of  the  incomplete 
state  of  our  knowledge  of  clays  and  clay  products.  We  still  have  much  to 
learn  about  the  properties  of  the  unburned  and  the  burned  clays  and  their 
products. 

Much  information  has  been  gathered  through  the  agencies  of  the 
American  Ceramic  Society  and  other  similar  organizations,  the  various 
geological  surveys,  industrial  laboratories,  and  research  conducted  at  the 
various  universities.  Through  cooperation  of  these  various  agencies,  stand- 
ard methods  of  testing  are  being  devised  and  standard  specifications  pre- 
pared, but  the  task  is  a large  one  and  is  made  particularly  difficult  because 
of  our  ignorance  of  much  that  is  fundamental  relating  to  the  material. 

One  of  the  benefits  which  may  be  attributed  to  the  recent  war  was  the 
impetus  given  to  the  investigation  of  these  problems.  As  consequences  of 
this,  not  only  has  the  knowledge  of  our  clay  resources  been  extended,  but 
much  has  been  learned  about  the  requirements  to  be  met  by  the  raw  mate- 
rials and  also  the  conditions  which  the  finished  product  should  satisfy.  A 
better  understanding  of  these  conditions  has  brought  about  a notable  improve- 
ment in  the  products. 

Any  economic  classification  of  clays  made  at  this  time  is  to  be  regarded 
as  only  tentative,  for  the  reason  previously  mentioned,  namely,  the  incom- 
plete state  of  our  knowledge  of  the  properties  of  the  raw  materials  which 
gives  them  especial  value  in  the  manufacture  of  certain  products.  Further, 
in  the  consideration  of  such  a classification  it  must  be  remembered  that  with 
the  exception  of  certain  products  of  the  cruder  sort,  it  is  the  practice  to 
blend  two  or  more  clays  which  are  commonly  of  quite  different  kinds,  with 
a view  to  obtaining  mixtures  which  may  be  formed  into  wares  without 
too  much  difficulty  or  loss,  and  which  will  possess  the  desired  properties. 
Therefore,  in  the  following  classification,  an  attempt  has  been  made  to  indi- 
cate what  may  be  called  the  primary  uses  or,  in  other  words,  those  for  which 
the  clay  is  particularly  adapted.  This  does  not  exclude  clays  from  uses  for 
purposes  not  specified.  For  example,  a superior  fire  clay  may  be  suited  for 
the  manufacture  of  common  brick.  Its  primary  usefulness,  however,  may 
be  regarded  as  for  firebrick  since  it  will  be  most  valuable  manufactured  into 
that  product. 


iRies,  H.,  Clays;  their  occurrence,  properties  and  uses:  p.  23,  1914. 


10 


ILLINOIS  FIRE  CLAYS 


A PROPOSED  CLASSIFICATION1 

The  clays  are  classified  for  use  according  to  the  physical  properties 
which  give  them  especial  value  for  specific  purposes. 

I.  Clays  Burning  White  or  Cream  Colored,  not  Calcareous 

A.  open  burning  clays,  i.  e.,  still  distinctly  porous  at  cone  15 

1.  Low  strength,  e.  g.,  residual  kaolins  such  as  those  from  North  Caro- 
lina 

2.  Medium  and  high  strength,  e.  g.,  secondary  kaolins  such  as  those  from 
Florida  and  Georgia 

Clays  of  the  open  burning  type  are  of  value  in  the  manufacture  of  pot- 
tery because  of  their  good  color  or  because  of  the  good  strength  and  good 
color.  These  clays  are  frequently  of  a good  or  high  degree  of  refractoriness. 
If  of  a good  color,  they  may  be  used  for  special  refractories  such  as  pots  for 
melting  optical  glass ; or  the  color  may  be  of  secondary  importance  and  the 
clays  may  be  valued  for  their  refractoriness  only 

B.  clays  burning  dense,  i.  e.,  become  nearly  or  completely  non-porous  between 
cones  10  and  15 

a.  Non-refractory  clays  : 

3.  Good  color,  medium  to  high  strength,  medium  shrinkage.  Uses : Pot- 
tery, including  certain  whiteware,  porcelains,  stoneware 

4.  Poor  color,  medium  to  high  strength,  medium  shrinkage.  Uses : Stone- 
ware, terra  cotta,  abrasive  wheels,  zinc  retorts,  face  brick,  saggars 

b.  Refractory  clays: 

5.  Good  color,  medium  to  high  strength,  medium  shrinkage.  Uses : Re- 
fractories, especially  for  glass,  if  they  do  not  overburn  seriously  for  5 
cones  higher.  Also  uses  stated  in  3 

C.  dense  burning  clays,  i.  e.,  become  nearly  or  completely  non-porous  between 
cones  5 and  10  and  do  not  overlburn  seriously  at  5 cones  higher  than  the  tem- 
perature at  which  minimum  porosity  is  reached 

a.  Non-refractory  clays: 

6.  Good  color,  medium  to  high  strength,  medium  shrinkage ; usually  reach 
minimum  porosity  between  cones  5 and  8.  Type : Ball  clays.  Uses : 
Pottery,  whiteware,  porcelain,  and  stoneware 

7.  Poor  color,  medium  to  high  strength,  medium  shrinkage.  Uses : Stone- 
ware, terra  cotta,  abrasive  wheels,  zinc  retorts,  face  brick,  saggars 

b.  Refractory  clays : 

8.  Non-porous  or  practically  so  at  cone  5;  do  not  seriously  overburn  for 
12  cones  higher ; highly  refractory ; softening  point  at  cone  31  or  higher ; 
bonding  strength  minimum  325  pounds  per  square  inch.  Use : Graphite 
cucibles  for  melting  brass.2 

9.  Non-porous  at  about  1275°  C.  (cone  8),  not  overfiring  at  1400°  C.  or 
higher.  Strength  and  softening  point  as  above2.  Use : Steel  crucibles 

10.  Become  dense  at  about  1275°  C.  (cone  8).  Do  not  overburn  below 
1425°  C.  Bonding  strength,  250  pounds  per  square  inch  or  higher.  Soft- 
ening point,  cone  29  or  higher2.  Use : glass  pots 

1This  classification  relates  only  to  the  uses  of  clays  for  burned  products  and  conse- 
quently no  consideration  is  given  to  its  uses  as  filler  for  paper  or  cloth,  as  a pigment,  etc. 

F'or  a definition  of  the  terms  “refractory"  and  “non-refractory”  as  used  in  this  classi- 
fication and  throughout  the  report,  see  page  13.  For  the  terms  “medium”  and  “high 
strength.’’  see  page  22  et  seq. 

2See  page  16. 


CLASSIFICATION  OF  CLAYS 


11 


II.  Buff  Burning  Clays 

A.  REFRACTORY  CLAYS 

a.  Open  burning,  i.  e.,  having  a porosity  of  5 per  cent  or  more  at  cone  15  or 
above : 

Indurated — non-plastic  or  slightly  plastic  unless  it 
has  been  weathered.  Type:  flint  clay. 

11.  Normally  aluminous;  maximum  alumina  40%.  Use:  Refractories 

12.  Highly  aluminous  ; alumina  exceeds  40%.  Type  : Diaspore  clay.  Uses: 
Refractories,  abrasives 

Plastic 

13.  Normally  siliceous;  maximum  silica  not  exceeding  65%.  Uses:  Fire- 
brick and  other  refractory  wares,  terra  cotta,  sanitary  ware,  glazed  and 
enamelled  brick  (see  specific  requirements  for  these  below) 

14.  Siliceous;  having  a silica  content  above  65%.  Type:  Many  of  the  New 
Jersey  fire  clays.  Uses:  Firebrick  and  other  refractories 

b.  Dense  burning  between  cones  10  and  15,  i.  e.,  attaining  a minimum  porosity 
of  5%  or  less  within  that  range: 

15.  Medium  to  high  strength.  Do  not  overburn  for  5 cones  higher  than 
point  of  minimum  porosity.  Uses:  Glass  pots  and  other  refractories; 
also  used  for  firebrick,  saggars  and  miscellaneous  refractories,  archi- 
tectural terra  cotta,  sanitary  ware,  enamelled  and  face  brick 

c.  Dense  burning,  i.  e.,  attaining  a porosity  of  5%  or  less  at  cone  10  or  lower: 

16.  See  8 

17.  See  9 

18.  See  10 

These  three  classes,  16,  17  and  18,  are  used  also  for  zinc  retorts,  fire- 
brick, saggars,  and  miscellaneous  refractories,  architectural  terra  cotta, 
sanitary  ware,  enamelled  and  face  brick 

B.  NON-REFRACTORY  CLAYS 

a.  Open  burning,  i.  e.,  do  not  attain  a porosity  of  5%  or  less  at  any  cone 
lower  than  cone  10 : 

19.  High  or  medium  strength.  Uses : Architectural  terra  cotta,  stoneware, 
yellow  ware,  face  brick,  sanitary  ware 

20.  Low  strength.  Use:  Brick 

b.  Dense  burning,  i.  e.,  attain  a porosity  of  less  than  5%  at  cones  lower  than  10  : 

21.  High  or  medium  strength.  Uses:  Architectural  terra  cotta,  stoneware, 
abrasive  wheels,  sanitary  ware,  face  brick,  paving  brick 

III.  Clays  Burning  Red,  Brown,  or  Other  Dark  Colors 

A.  open  burning  clays,  i.  e.,  those  that  do  not  attain  low  porosity  at  any  tem- 

perature short  of  actual  fusion 

22.  Medium  or  high  strength.  Uses : Brick,  drain  tile,  hollow  blocks,  flower 
pots,  pencil  clays,  ballast 

23.  Low  strength.  Use : Brick 

B.  dense  burning  clays 

a.  Having  a long  vitrification  range  (5  cones)  : 

24.  High  or  medium  strength.  Uses : Conduits,  sewer  pipe,  paving  brick, 
floor  tile  or  quarries,  electrical  porcelain,  cooking  ware,  silo  block,  art 
ware,  face  brick,  architectural  terra  cotta,  roofing  tile 

25.  Low  strength.  Uses:  As  dust  body  in  the  manufacture  of  electrical 
porcelain,  floor  tile,  building  brick 


12 


ILLINOIS  FIRE  CLAYS 


b.  Having  a short  vitrification  range : 

26.  High  or  medium  strength.  Uses : Building  brick,  face  brick,  hollow 
block,  flower  pots 

c.  Fusing  at  a low  temperature,  approximately  cone  5,  to  form  a glass: 

27.  Slip  clays 

IV.  Clays  Burning  Dirty  White,  Cream  White,  or  Yellowish  White 

28.  Containing  calcium  or  magnesium  carbonate  or  both.  Never  reach  very 
low  porosity.  Have  a very  short  heat  range.  Use : Common  brick 

Types  and  Uses  of  Clays 

In  the  “Clay  Classification/’  references  are  made  to  certain  types  of 
clays  which  have  been  found  adapted  to  special  uses.  In  the  following  brief 
descriptions  an  endeavor  is  made  to  state  the  characteristics  of  such.  How- 
ever, the  fact  that  a clay  is  designated  a terra  cotta  clay  or  a sanitary  ware 
clay,  for  example,  does  not  necessarily  mean  that  the  clay  constitutes  a dis- 
tinct type,  and  the  attempt  has  been  merely  to  describe  the  kind  of  material 
which  is  sought  for  the  use  indicated.  As  a matter  of  fact,  for  many  pur- 
poses it  is  quite  impossible  to  define  the  characteristics  closely. 

KAOLIN  OR  CHINA  CLAY 

The  true  kaolin  is  residual  in  its  origin.  It  has  a low  degree  of  plasticity, 
low  strength,  low  shrinkage  both  in  drying  and  burning,  and  after  purification 
by  washing  is  refractory.  The  term  kaolin  is  used  in  this  country  for  the 
same  type  of  material  as  that  designated  by  the  English  potter  as  china  clay, 
and  kaolins  are  used  for  the  same  purposes  as  china  clays.  Since  there  would 
be  an  advantage  in  introducing  a distinction  between  the  terms,  it  has  been 
proposed  to  restrict  the  term  kaolin  to  the  crude  material  and  china  clay  to 
that  which  has  been  purified  for  the  market.1 

Kaolins  do  not  always  burn  white.  Some  that  are  so  badly  stained  that 
they  are  unsuited  for  use  by  the  potter,  may  have  considerable  value  if 
refractory.  True  kaolins  have  not  been  found  in  the  State,  nor  is  there 
much  likelihood  of  such  a discovery.  The  so-called  kaolins  of  Union  County 
are  misnamed. 


SECONDARY  KAOLINS 

These  differ  in  origin  from  the  true  kaolins  in  that  they  have  been 
transported  from  the  place  of  origin  by  water  and  laid  down  in  extensive 
beds.  They  are  more  plastic,  stronger,  and  have  higher  shrinkages.  They 
burn  white,  although  not  quite  equalling  the  best  residual  kaolins.  They 
are  adapted  to  uses  similar  to  those  of  the  true  kaolins. 

iMellor,  J.  W.,  A note  on  the  nomenclature  of  clays : Trans.  English  Ceramic  Soc. 
VIII,  p.  23. 


TYPES  AND  USES 


13 


BALL  CLAY 

These  are  highly  plastic,  strong  clays  which  burn  cream  white  or  a 
very  light  buff  and  vitrify  between  cones  5 and  10,  so  that  they  are  non- 
absorbent. No  ball  clays  have  been  located  in  Illinois,  although  the  so-called 
kaolins  of  Union  County  have  the  characteristics  of  this  type.  It  is  possible 
that  some  of  the  stoneware  clays  of  the  State  may  he  of  a sufficiently  good 
quality  after  washing  to  permit  their  use  for  some  of  the  purposes  for  which 
ball  clay  is  suitable.  Ball  clays  are  sedimentary  in  their  origin.  The  drying 
shrinkage  is  ordinarily  less  than  10  per  cent;  the  modulus  of  rupture  as 
determined  by  the  cross-breaking  strength  test  varies  between  200  and  500 
pounds  the  square  inch,  with  an  average  of  350  pounds ; the  tensile  strength 
per  square  inch  varies  between  125  and  150  pounds;  the  total  shrinkage  at 
cone  10  varies  between  16  and  20  per  cent.  The  water  of  plasticity  varies 
between  27  and  43  per  cent  with  an  average  of  32.6  per  cent. 

REFRACTORY  CLAYS 

Clays  are  designated  as  refractory  if  they  are  capable  of  withstanding 
high  temperatures  without  showing  signs  of  fusion  such  as  deformation, 
i.  e.,  loss  of  shape,  or  softening  to  a fluid  state. 

Since  all  clays  are  able  to  withstand  relatively  high  temperatures,  and 
since  no  standard  has  yet  been  adopted,  it  becomes  necessary  to  define  more 
precisely  what  is  meant  by  the  term  refractory  clay.  Purdy1  and  Bleininger2 
have  suggested  cone  26,  and  Ries3  has  named  cone  31  as  the  boundary 
between  the  refractory  and  the  semi-refractory  clays  with  cone  27  as  the 
lower  limit  for  the  latter  clays.  For  purposes  of  this  bulletin,  all  clays  which 
fuse  at  cone  27  or  higher  are  considered  to  be  refractory  and  those  which 
fuse  at  cone  33  or  above  are  classified  as  highly  refractory. 

The  term  fireclay  has  come  to  be  used  in  a broader  sense  than  is  con- 
noted by  mere  refractoriness.  It  is  now  applied,  at  least  in  the  middle  west, 
to  clays  which  have  some  of  the  characteristics  of  the  true  fireclays  without 
regard  to  their  ability  to  withstand  very  high  temperatures.  Commercially 
they  have  been  divided  into  three  classes  which  are  known  as  No.  1,  No.  2, 
and  No.  3.  The  separation  into  these  three  grades  has  to  a large  extent 
been  left  to  the  convenience  of  the  miner  who  wishes  to  make  a distinction 
between  materials  but  lacks  the  means  for  differentiating  explicitly.  Some 
attempt  has  been  made  to  standardize  these  terms:  for  example,  Bleininger4 
prescribes  the  lower  limit  of  the  softening  temperature  of  No.  1 fireclay  as 


iPurdy,  Ft.  C.,  and  DeWolf,  F.  W.,  Preliminary  investigation  of  Illinois  fire  clays*. 
111.  State  Geol.  Survey  Bull.  4,  p.  149,  1907. 

2Bleininger,  A.  V.,  The  testing  of  clay  refractories  : U.  S.  Bureau  of  Standards  Tech. 

Paper  No.  7,  p.  15,  1912. 

3Ries,  H„  The  clays  and  clay  industry  of  New  Jersey:  New  Jersev  Geol.  Survey, 
Final  Rept.  Vol.  VI,  p.  311,  1904. 

4Bleininger,  A.  V.,  The  testing  of  clay  refractories:  U.  S.  Bureau  of  Standards 
Tech.  Paper  No.  7,  p.  44,  1912. 


14 


ILLINOIS  FIKE  CLAYS 


cone  32 ; and  further,  according  to  Purdy,1  the  time-temperature  rate  of  vitri- 
fication is  very  slow  so  that  it  attains  a low  porosity  only  at  a very  high 
temperature,  if  at  all. 

The  term  No.  2 fireclay  is  peculiar  to  the  middle  west.  Not  infrequently 
it  is  used  by  a clay  miner  to  designate  a grade  which  is  inferior  to  the  best 
which  he  is  mining.  However,  the  term  is  most  frequently  employed  to  desig- 
nate a clay  which  burns  to  a light  color — a cream,  buff,  or  light  tan — and 
attains  a low  porosity  at  some  temperature  between  cone  5 and  cone  11. 
These  limits  have  been  arbitrarily  set  by  the  writer  since,  with  the  exception 
of  some  work  done  by  Purdy2  no  attempt  has  been  made  to  define  the  term 
with  exactness.  These  clays  are  somewhat  less  refractory  than  the  No.  1 
grade  and  burn  to  a dense  structure  which  makes  them  unsuited  as  the  chief 
clay  component  for  the  manufacture  of  the  best  grade  of  firebrick.  The 
fact  that  the  term  No.  2 fireclay  in  some  cases  connotes  “second-grade”  and 
the  fact  that  use  of  this  clay  in  the  manufacture  of  this  particular  product 
is  limited,  should  not  be  misunderstood  and  the  class  consequently  under- 
valued, for  amongst  these  No.  2 fireclays  some  of  the  most  useful  of  the 
fireclays  are  found.  The  refractory  clays  of  this  class  which  have  high 
strength  are  indispensable  in  the  manufacture  of  crucibles,  zinc  retorts,  and 
glass  refractories,  and  those  of  good  strength  are  necessary  as  the  bonding 
agent  for  the  No.  1 fireclays  in  the  manufacture  of  the  best  grade  firebrick. 

According  to  Mr.  Purdy3  the  No.  2 fireclays  may  fuse  as  low  as  cone 
16  and  may  be  as  high  as  cone  26,  which  is  the  minimum  refractoriness  of  a 
No.  1 fireclay.  Bleininger4  states  that  “There  is  no  sharp  distinction  between 
the  No.  1 and  the  No.  2 fireclays,  and  any  lower  limits  that  may  be  set  must 
be,  in  the  nature  of  the  case,  arbitrary.”  Further  he  states5  that  “cone  28 
might  be  considered  the  limit  below  which  a satisfactory  bond  clay  should 
not  soften.”  This  is  not  incompatible  with  the  experience  of  Mr.  Purdy6 
since  he  found  that  the  “fusion  point  [of  the  No.  1 clays]  in  the  majority 
of  cases  does  not  exceed  that  of  the  so-called  No.  2 fireclays.” 

It  would  seem  from  the  above  references  that  there  is  much  confusion 
in  the  use  of  the  term  No.  2 fireclay.  In  the  opinion  of  the  writer,  the  term 
should  be  abandoned  in  technical  literature  and  its  use  otherwise  discouraged 
for  two  reasons:  (1)  it  carries  with  it  an  implication  of  inferiority  which 
is  most  unfortunate  since  many  of  the  clays  which  may  be  grouped  under 
this  class  are  quite  as  valuable  and  indispensable  as  those  which  we  call  the 
No.  1 fireclays;  and  (2)  it  makes  no  distinction  between  the  refractory  clays 


iRolfe,  C.  W.,  Purdy,  R.  C.,  Talbot,  A.  N.,  and  Baker,  I.  O.,  Paving  brick  and  paving 
brick  clays  of  Illinois.  111.  State  Geol.  Survey  Bull.  9,  p.  270,  1908. 

-Op.  eir..  p.  272. 

3Purdv.  R.  <’..  and  PeWolf,  P.  W..  Preliminary  investigations  of  Illinois  fire  clavs  : 
111.  State  Geol.  Survey  Bull.  4,  p.  139,  1907. 

4Bleininger.  A.  V.,  The  testing  of  clay  refractories:  U.  S.  Bureau  of  Standards  Tech. 
Paper  No.  7,  p.  45,  1912. 

5Op.  cit.,  • p.  45. 

6Purdy.  R.  (".,  and  PeWolf,  P.  W..  Preliminary  investigations  of  Illinois  fire  clavs : 
111.  State  Geol.  Survey  Bull.  4,  p.  139,  1907. 


TYPES  AND  USES 


15 


and  those  which  are  non-refractory.  In  other  words,  the  term  is  used  to 
include  those  clays  which  are  not  fireclays  in  the  strict  interpretation  of  the 
term.  It  seems  to  the  writer  to  be  more  desirable  to  use  a terminology  such 
as  proposed  in  the  classification  on  pages  10  to  12. 

The  use  of  the  term  No.  3 fireclays  seems  to  be  equally  unfortunate. 
These  have  been  described  by  Purdy1  as  seldom  having  fusion  points  exceed- 
ing cones  16  and  17.  He  differentiates  them  from  the  No.  2 fireclays  on  the 
basis  of  the  rate  of  temperature-porosity  changes.  Since  the  basis  of  the 
distinction  is  not  refractoriness  and  the  type  clay  is  non-refractory,  it  would 
therefore  be  better  to  avoid  the  use  of  the  word  fireclay.  There  are  refrac- 
tory clays  which  have  a rate  of  temperature-porosity  change  which  would 
place  them  in  this  group.  Because  of  other  physical  properties,  they  are 
adapted  for  use  for  specific  purposes  which  gives  them  an  especial  value : 
for  example,  the  crucible  clays  and  those  used  for  zinc  retorts.  It  would 
seem  a mistake  to  group  this  type  indiscriminately  with  the  non-refractory 
clays  simply  because  of  the  rate  of  temperature-porosity  change. 

The  method  of  studying  clays  by  means  of  the  temperature-porosity 
changes  has  been  found  to  be  exceedingly  useful,  although  the  scheme  of 
classification  which  Mr.  Purdy  proposed  as  based  upon  the  rate  of  these 
changes  has  been  subject  to  criticism  by  later  investigators.2  Some  of  the 
difficulties  encountered  were  anticipated  by  him  in  the  statement  “it  is  possi- 
ble that  broader  limits  will  be  determined  when  more  and  a larger  variety  of 
clays  are  tested.”  Beecher3  in  his  study  of  Iowa  clays  attempted  to  use  the 
proposed  classification  but  found  several  marked  irregularities.  It  is  difficult 
to  understand  these  with  our  present  limited  knowledge  of  the  mineralogical 
and  chemical  constitution  of  clays.  However,  it  points  to  the  necessity  for 
broader  knowledge  of  these  matters.  As  previously  stated,  the  method  of 
study  has  been  widely  adopted  and  has  been  very  fruitful. 


PLASTIC  REFRACTORY  BOND  CLAYS 

These  clays  are  used  in  the  manufacture  of  crucibles,  glass  pots,  zinc 
retorts,  and  miscellaneous  glass  house  refractories.  They  are  used  in  mix- 
tures with  less  plastic  clays  and  with  non-plastic  materials.  According  to 
the  investigations  of  A.  V.  Bleininger  and  his  associates  at  the  U.  S. 
Bureau  of  Standards,4,5  the  requirements  to  be  met  by  these  clays  are  as 
follows : 


iRolfe,  C.  W.,  Purdy,  R.  C.,  Talbot,  A.  N.,  and  Baker,  I.  O. ; Paving  brick  and 
paving  brick  clays  of  Illinois:  111.  State  Geol.  Survey  Bull.  9,  p.  272,  1908. 

-Bleininger,  A.  V..  The  testing  of  clay  refractories  : U.  S.  Bureau  of  Standards  Tech. 

Paper  No.  7,  p.  44,  1912. 

3Beecher,  Milton  F.,  Iowa  State  College  Eng.  Exp.  Station  Bull.  40,  p.  88,  1915. 

4Bleininger,  A.  V.,  Properties  of  American  bond  clays,  etc.;  U.  S.  Bureau  of 
Standards,  Tech.  Paper  No.  144,  1920. 

5Bleinin$rer,  A.  V.,  and  Schurecht,  H.  G.,  Properties  of  some  European  plastic  fire 
clays:  U.  S.  Bureau  of  Standards  Tech.  Paper  No.  79,  1916. 


16 


ILLINOIS  FIRE  CLAYS 


The  siliceous  clays  and  those  for  glass  refractories  should  not  soften  below 
cone  30;  for  severe  service  the  softening  point  should  be  above  cone  31.  In 
consideration  of  the  clay  having  other  desirable  properties,  some  modification 
of  this  may  be  made ; for  example,  a very  well  known  foreign  clay  which 
formerly  was  widely  used  softened  at  about  cone  28.  The  water  of  plasticity 
varies  between  30  and  45  per  cent;  the  linear  drying  shrinkage  should  lie 
between  6.5  and  10  per  cent;  the  plasticity  should  be  high;  the  strength  as 
measured  in  terms  of  bonding  power  expressed  as  modulus  of  rupture, 
obtained  by  testing  a mixture  of  equal  parts  of  the  clay  and  grog  is  325 
pounds  per  square  inch  for  Class  A,  and  225  pounds  per  square  inch  for 
Class  B.  A classification1  made  according  to  the  burning  conduct  is  as  fol- 
lows : 

1 —  Burn  dense  at  about  1150°  C.  (2102°  F.)  and  not  overfired  at 
1400°  C.  (2552°  F.).  Especially  suited  for  graphite  crucibles  for 
brass  melting. 

2 —  Burn  dense  at  about  1275°  C.  (232 7°  F.)  and  do  not  overfire  at 
1400°  C.  (2552°  F.)  or  higher.  Suited  for  crucibles  for  steel  and 
valuable  for  glass  refractories  if  they  do  not  overburn  below  1425° 
C (2597°  F.). 

3 —  Burn  dense  at  1425°  C.  (2597°  F.)  or  higher.  May  overfire  at 
1450°  C.  (2647°  F.)  or  above.  Valuable  for  glass  refractories. 

4—  Burn  dense  between  1150°  C.  (2102°  F.)  and  1300°  C.  (2372°  F.) 
and  have  short  heat  range.  Unsuited  for  refractory  bond  clay. 

The  above  classification  applies  to  clays  burned  at  the  rate  of  20°  C. 
(36°  F.)  per  hour  above  800°  C.  (1472°  F.). 

According  to  M.  G.  Babcock2  the  requirements  of  a zinc  retort  clay  are: 
Considerable  strength  and  bonding  power ; a linear  shrinkage  between  4 and 
6.5  per  cent;  a porosity-temperature  range  from  10  per  cent  at  1150°  C. 
(2102°  F.)  to  about  5 per  cent  at  1250°  C.  (2282°  F.)  ; it  should  not  over- 
burn lower  than  1400°  C.  (2552°  F.)  ; deformation  point  should  not  be 
below  cone  30. 


ARCHITECTURAL  TERRA  COTTA  CLAYS 
These  are  similar  to  the  stoneware  clays.  They  should  be  free  from 
pyrites,  concretions,  soluble  salts,  gypsum,  coaly  forms  of  carbon,  and  other 
objectionable  forms  of  foreign  materials,  because  the  clays  are  rarely  washed 
before  using.  The  presence  of  free  silica  in  excess  of  3 per  cent  in  the  form 
of  grains  which  will  not  pass  a 200  mesh  sieve  is  considered  objectionable 
by  one  firm  of  manufacturers.  The  red-burning  clays  are  seldom  used  for 
this  purpose  since  they  are  not  as  well-suited  as  are  the  light  cream  or  light 

iBleininger,  A.  V.,  and  Loomis,  G.  A.,  The  properties  of  some  American  bond  clays : 
Trans,  of  the  American  Ceramic  Soc.,  Vol.  19,  p.  606,  1917. 

2Babcock,  M.  G.,  Refractories  for  the  zinc  industry  : Jour.  Am.  Cer.  Soc.,  Vol.  2,  p.  SI, 

1919. 


TYPES  AND  USES 


17 


buff  colors  for  the  type  of  decoration  ordinarily  applied  to  this  product. 
The  clays  should  have  a good  plasticity  and  be  strong,  but  those  which  are 
sticky  or  rubbery  when  in  the  plastic  condition  are  avoided.  Since  the  terra 
cotta  bodies  are  compounded  of  mixtures  of  clays  and  grog  (i.e.,  ground 
burned  clay),  the  manufacturer  may  control  the  shrinkages  very  readily, 
but  it  is  desirable  that  the  shrinkages  of  the  clays  used  should  be  low  or 
medium.  The  clays  should  slake  readily  when  wet  with  water,  so  that  they 
may  be  brought  to  a uniformly  plastic  mass  without  delay.  Usually  two  or 
more  clays  are  used  in  the  batch.  One  of  these  at  least  should  burn  dense 
at  some  temperature  within  the  ordinary  range,  namely,  between  cones  1 and 
6,  and  the  minimum  porosity  should  be  10  per  cent  or  lower.  The  clay 
should  have  a sufficiently  long  heat  range  at  the  cone  temperature  of  minimum 
porosity  so  that  there  will  not  be  any  danger  of  overburning  in  the  commer- 
cial kiln.  These  dense  burning  clays  should  not  warp  or  crack  in  the  drying 
or  burning  process.  The  other  clay  used  will  be  of  the  open  burning  type. 

STONEWARE  CLAYS 

These  are  sedimentary  clays  which  have  good  plasticity  and  strength, 
burn  to  a cream  or  light  tan  color,  and  reach  a low  porosity  between  cones 
5 and  9.  They  should  be  free  from  substances  which  will  give  rise  to  the 
formation  of  soluble  salts.  It  is  desirable  that  the  clays  be  free  from  con- 
cretions, pyrites,  coaly  forms  of  carbon,  and  other  substances  which  may 
interfere  with  the  use  of  the  clay,  although  washing  of  the  clay,  which  is. 
frequently  resorted  to  preparatory  to  use,  will  remove  them.  A comparison 
of  the  data  regarding  the  stoneware  clays  used  in  different  parts  of  the 
United  States  indicates  that  the  physical  properties  are,  on  the  average, 
as  follows : The  water  of  plasticity  is  from  18  to  37  per  cent,  though  the 
usual  amount  is  35  per  cent;  the  drying  shrinkage  varies  between  5 and  13 
per  cent,  and  the  average  is  about  8 per  cent;  the  strength  of  the  clay  as 
measured  by  the  crossbreaking  test1  varies  between  125  and  400  pounds  with 
the  average  at  about  250  pounds  per  square  inch ; the  tensile  strength  varies 
between  100  and  300  pounds  with  an  average  of  150  pounds;  the  minimum 
porosity  attained  during  burning  is  between  5 and  10  per  cent,  which  may 
be  reached  between  cones  5 and  10;  the  average  burning  shrinkage  is  prob- 
ably about  8 per  cent. 

SAGGAR  CLAYS 

Two  types  of  clays  are  used  in  mixtures  for  the  manufacture  of  these 
wares,  namely,  an  open  burning  clay  of  good  refractoriness,  and  a clay  of 
lower  refractoriness  which  will  burn  dense  at  a low  temperature.  It  is 
desirable  that  both  types  should  have  good  plasticity  and  good  strength, 
although  these  properties  may  be  the  characteristics  of  only  one  of  the  clays 
used.  It  is  important  that  the  clays  do  not  contain  pyrites,  concretionary 


il.  e.,  modulus  of  rupture. 


18 


ILLINOIS  FIRE  CLAYS 


matter,  or  other  foreign  material  which  may  cause  damage  to  the  wares 
placed  in  the  saggars  for  burning.  The  shrinkages  of  the  clays  are  not 
important  since  the  mixtures  contain  a very  considerable  amount  of  grog 
and,  moreover,  small  variations  in  size  are  of  no  moment.  Unless  the 
saggars  are  to  be  used  at  very  high  temperatures,  it  is  not  necessary  to  use 
high  grade  refractory  clays.  It  is  quite  essential,  however,  that  the  clays 
should  be  suitable  for  use  in  mixtures  which  are  subjected  to  heavy  loads 
at  high  temperatures.  Knowledge  of  the  fundamentals  of  good  saggar 
making  is  as  yet  in  a rudimentary  stage,  and  there  is  a great  divergence  in 
the  practice  of  potters  in  the  choice  of  materials  and  their  proportions. 

SANITARY  WARE  CLAYS 

The  clays  used  in  the  manufacture  of  such  wares  as  bath  tubs,  wash 
trays,  and  sinks,  are  similar  to  those  used  in  the  manufacture  of  terra  cotta. 

PAVING  BRICK  CLAYS 

The  requirements  to  be  met  by  these  clays  are  good  plasticity  so  that 
they  may  be  formed  as  brick  by  the  auger  machine ; little  or  no  tendency 
to  laminate;  good  strength;  safe  drying  properties  so  that  they  will  not  warp 
or  crack  during  that  process ; a low  carbon  and  sulphur  content  so  that  they 
may  be  readily  and  safely  oxidized  during  the  burning  process ; little  or  no 
concretionary  material ; the  color  of  the  burned  ware  should  be  a good  red 
in  order  to  meet  the  usual  requirements  of  the  trade,  although  paving  bricks 
are  made  also  of  clays  burning  to  a light  color;  the  minimum  porosity  should 
be  approximately  5 per  cent  or  less  and  this  should  be  attained  with  a suffi- 
ciently wide  heat  range  so  that  there  will  be  no  danger  of  overburning  in 
the  ordinary  commercial  kiln ; the  product  must  develop  a sufficient  degree 
of  toughness  to  meet  the  usual  tests ; the  linear  drying  shrinkage  may  vary 
considerably,  but  the  ordinary  maximum  is  8 per  cent  and  the  average  is  6 
per  cent;  the  water  of  plasticity  of  typical  paving  brick  clays  is  17  per  cent. 

FACE  BRICK  CLAYS 

Clays  of  a great  variety  are  used  for  this  purpose  and  the  requirements 
which  must  be  met  may  be  stated  only  in  a general  way.  For  the  purpose 
of  manufacturing  by  the  plastic  process,  which  is  that  most  generally  used, 
the  clay  must  be  of  a sort  which  will  flow  readily  through  the  die  of  the 
brick  machine.  No  marked  development  of  lamination  should  occur.  The 
clay  should  have  a fair  or  good  strength  in  the  dry  condition.  It  should 
dry  readily  and  safely  without  a tendency  to  warp  or  crack.  The  usual 
shrinkage  is  from  6 to  8 per  cent,  although  it  varies  widely.  The  appearance 
of  a scum,  whitewash,  or  efflorescence  of  any  kind  at  this  or  subsequent 
stages  in  the  manufacture  is  objectionable.  The  clay  should  be  practically 
free  from  minerals  of  a harmful  kind,  size,  or  quantity,  as  for  example, 
calcium  carbonate  in  its  various  forms,  pyrites,  and  concretionary  iron.  The 
clays  should  burn  hard  and  strong  without  warping,  blistering,  pitting,  etc. 


CONSERVATION 


19 


They  should  attain  a low  per  cent  of  absorption  at  a temperature  which  is 
commercially  practicable.  This  varies  widely  according  to  the  type  of  mate- 
rial and  may  be  said  not  to  exceed  cone  8 and  usually  lies  below  cone  1. 
The  clays  should  have  a sufficiently  wide  heat  range  to  permit  the  necessary 
degree  of  vitrification  without  danger  of  overburning  and  the  variations  in 
color  throughout  the  burn  should  be  of  a sort  both  as  to  shade  and  variety 
as  to  permit  satisfactory  grading. 

Conservation  of  Clays 

We  have  been  accustomed  to  regard  the  supply  of  our  better  grades 
of  clays  as  practically  inexhaustible.  Considering  the  great  area  of  the 
whole  country  and  the  large  portion  still  unexplored  economically,  this  may 
be  accepted  as  true.  However,  in  those  states  which  are  most  largely  given 
over  to  industrial  pursuits,  it  is  scarcely  wise  to  make  this  assumption. 
While  it  is  true  that  we  have  large  areas  with  great  tonnages  in  the  process 
of  utilization  and  other  areas  known  and  unknown  yet  to  be  exploited,  still 
we  should  not  evade  the  fact  that  in  some  important  districts  the  end  is  in 
sight.  It  is  wise,  therefore,  to  have  in  mind  the  importance  of  conserving 
the  supply  of  the  better  grades  of  clays.  This  may  be  done  by  obtaining 
a complete  knowledge  of  the  extent  and  character  of  our  clay  resources ; 
by  a more  precise  knowledge  of  the  requirements  of  the  raw  materials  for 
the  manufacture  of  the  various  wares;  by  less  wasteful  methods  of  mining; 
by  the  use  of  methods  of  purification  to  render  clays  serviceable  which 
would  otherwise  be  unavailable  for  use ; by  the  adoption  of  the  practice  of 
blending  clays  from  certain  areas  or  districts  so  that  there  would  be  a more 
complete  utilization  of  the  output  from  small  mines  of  the  region  or  of 
certain  strata  of  clays ; by  the  avoidance  of  the  practice  of  using  superior 
material,  either  the  raw  material  or  the  finished  product,  where  an  inferior 
grade  would  suffice. 

As  an  instance  of  the  importance  of  a more  adequate  knowledge  of  our 
clay  resources,  we  may  cite  the  diaspore  deposits  of  Missouri.  For  many 
years  flint  clay  deposits  in  certain  counties  of  that  state  have  been  operated. 
A peculiar  rough  type  of  clay  found  in  those  pits  was  regarded  as  detri- 
mental or  worthless,  and  abandoned  pits  may  be  found  today  where  large 
bodies  of  it  were  left.  Within  the  past  three  years,  this  material  has  been 
found  to  be  of  exceptional  interest  and  value  because  of  the  extraordinarily 
high  content  of  alumina.1 

The  Physical  Properties  and  the  Methods  of  Testing  the  Clays 

The  methods  of  testing  employed  were,  with  few  exceptions,  those  rec- 
ommended tentatively  by  the  American  Ceramic  Society’s  Committee  on 
Standards  in  its  report  of  1918. 


iBuehler,  H.  A.,  Biennial  Report  of  the  State  Geologist  of  Missouri,  p.  18,  1919. 


zw 


20 


ILLINOIS  FIRE  CLAYS 


^ a 


<v 

Vh 

CJ 

cn 

a <u 

^ JS 
'*■’  a 
<u  ^ 

rt  O c 
g,  to  .o  rt 

cn  £ Q w 
W fe  O K 


Fig.  44.  Hand  plunger  machine  for  molding  briquets. 


METHODS  OF  TESTING 


21 


PRELIMINARY  PREPARATION 

The  quantity  of  each  sample  collected  by  the  field  geologist  and  sent 
to  the  laboratory  approximated  fifty  pounds  weight,  but  was  less  when  spe- 
cial circumstances  made  a smaller  amount  necessary,  as  in  the  case  of 
samples  gathered  by  boring  with  an  auger. 

After  a careful  inspection  of  the  dried  material,  in  which  observations 
were  made  as  to  its  general  character,  its  degree  of  homogeneity,  and  the 
presence  of  easily  distinguishable  minerals,  organic  matter,  and  other  impuri- 
ties, the  sample  was  crushed  by  passing  through  a set  of  rolls  excluding,  of 
course,  any  pebbles  or  lumps  of  an  obviously  foreign  nature.  The  occur- 
rence of  pebbles  or  foreign  material  was  quite  unusual.  This  crushing  oper- 
ation was  limited  strictly  to  the  breaking  down  of  the  larger  lumps  of  clay 
and  no  grinding  was  done. 

The  powdered  clay  was  passed  through  a twenty-mesh  sieve,  and  the 
fines  were  moistened  with  a sufficient  quantity  of  water  to  permit  the  working 
of  the  mass  into  a plastic  condition  of  the  right  consistency  to  be  molded 
into  the  test  pieces.  The  determination  of  the  correct  consistency  was 
dependent  upon  the  judgment  of  the  operator.  Sometimes  a few  trials  were 
necessary  in  order  to  arrive  at  the  proper  condition.  Since  plastic  clays 
are  workable  with  a fairly  wide  range  of  water  content,  it  will  be  noted 
in  the  reports  upon  the  tests  of  clays  that  in  some  instances  a certain  amount 
of  variation  occurs  with  the  same  clay.  Thorough  kneading  or  wedging, 
as  it  is  called,  was  employed  in  order  to  insure  a uniformity  in  the  mass. 

THE  TEST  PIECES 
FORMATION 

The  pieces  required  for  the  testing  were  formed  by  one  or  the  other 
of  two  methods.  The  method  ordinarily  used  was  to  place  the  plastic  mass  in 
the  barrel  of  a piston  press  and  to  force  the  clay  to  flow  out  through  a die 
having  an  opening  one  inch  square.  The  bar  of  clay  thus  formed  was  cut 
into  pieces  about  four  inches  long. 

This  apparatus  (see  Fig.  44)  is  the  same  one  as  described,  and  used  in 
the  “Tests  on  Clay  Materials  Available  in  Illinois  Coal  Mines,”  published 
by  the  Illinois  State  Geological  Survey  as  Bulletin  18  of  the  Cooperative 
Mining  Investigations  series. 

This  method  furnished  also  a means  for  estimating  the  relative  ease 
or  difficulty  with  which  a clay  would  flow  through  a die,  a factor  which  is 
of  importance  in  some  lines  of  manufacture. 

The  alternative  method  was  to  form  a roll  of  clay  of  the  approximate 
dimensions  of  a small  brass  mold  and  to  tamp  the  roll  into  the  mold,  taking 
care  to  have  it  filled  completely.  The  piece  thus  formed  was  of  the  same 
size  as  that  formed  by  squeezing  through  the  die. 


22 


ILLINOIS  FIRE  CLAYS 


DRYING 

The  test  pieces  were  dried  carefully  by  keeping  them  for  a period  of 
several  hours  at  the  room  temperature,  then  in  a drier  at  a temperature 
of  100°  F.,  and  finally  at  a temperature  of  212°  F. 

raw  clays:  their  properties  and  methods  of  testing 

SHRINKAGE 

Shrinkage  is  the  contraction  which  takes  place  in  a clay  during  the 
drying  or  the  burning  of  the  same.  In  the  former  case,  it  is  due  to  the 
loss  of  the  water  which  has  been  introduced  to  render  it  plastic  and  which 
surrounds  and  separates  the  particles.  The  amount  of  the  shrinkage  varies 
widely  and  may  be  classified1  as  follows : 

Per  cent 

Low  0 — 3 

Medium  Low  3.1 — 6 

Medium  6.1 — 9 

Medium  High  9.1 — 12 
High  12.1  and  upwards 

Excessive  shrinkage  will  render  a clay  unfit  for  use  for  many  purposes 
and  often  causes  warping  or  cracking. 

Linear. — Immediately  after  forming  each  piece,  it  was  marked  for 
identification  and  shrinkage  marks  were  made  upon  one  face  spaced  3*4 
inches  apart.  After  the  completion  of  the  drying,  the  pieces  were  again 
measured  in  order  to  determine  the  amount  of  linear  shrinkage,  which  was 
calculated  as  follows : 

_ , _ . , Length  of  plastic  piece— Length  of  dry  piece 

Percentage  of  Linear  Shrinkage  = - — : X 100 

Length  of  dry  piece 

In  many  cases  the  linear  shrinkage  is  also  expressed  in  terms  of  the 
plastic  length,  as  for  example : 

Length  of  plastic  piece— Length  of  dry  piece 

Percentage  of  Linear  Shrinkage  s : ; X 100 

Length  of  plastic  piece 

Volume. — The  determination  of  the  volume  shrinkage  was  made  in  many 
cases.  It  was  done  by  means  of  a volumeter  which  is  described  later  (see 
page  29).  The  results  were  calculated  as  follows: 

Percentage  of  Volume  Shrinkages 

Volume  of  plastic  piece  — Volume  of  dry  piece  ^ 
Volume  of  dry  piece 

The  method  used  is  more  refined  than  that  employed  for  linear  shrink- 
age and  consequently  the  results  are  more  accurate. 

1A  slightly  modified  form  of  the  classification  given  by : Watts,  A.  S.,  Classification  of 
clays  on  a ceramic  basis:  Jour.  Am.  Cer.  Soc.,  Vol.  3,  p.  247,  1920. 


METHODS  OF  TESTING 


23 


WATER  OF  PLASTICITY 


The  amount  of  water  required  for  addition  to  a clay  to  render  it  readily 
workable  is  known  as  the  “Water  of  Plasticity.”  It  varies  widely  in  different 
clays,  depending  upon  the  fineness  of  grain  and  relative  amount  and  char- 
acter of  the  colloidal  content.  It  varies  also  with  the  same  clay.  In  general, 
the  more  plastic  clays  have  the  larger  content  of  water  of  plasticity  and 
exhibit  the  widest  variations  in  amounts  for  the  individual  clays.  They  also 
show  the  greatest  strength  in  the  dried  state.  The  following  table1  shows 
the  water  of  plasticity  content  of  some  typical  clays  and  shales : 


Per  cent 


Galesburg  Shale  26.7 

English  Ball  Clay  M.  and  M.  No.  1 49.3 

Tennessee  Ball  Clay  No.  3.. 52.5 

English  China  Clay 44.1 

Georgia  Kaolin  26.2 

Florida  Kaolin  45.2 

North  Carolina  Kaolin 34.2 


Good  working  properties 
Very  plastic,  rather  sticky 
Very  plastic,  rather  sticky 
Fairly  plastic 
Very  plastic,  rather  sticky 
Good  plasticity,  rather  sticky 
Slightly  plastic,  sticky 


The  calculation  of  the  water  of  plasticity  was  made  as  follows: 


Percentage  of  Water  of  Plasticity  = 

Weight  of  plastic  clay— Weight  of  clay  dried  at  212c 
100  X — — 


Weight  of  clay  dried  at  212°  F. 


The  water  of  plasticity  consists2  of  the  “Shrinkage  Water”  which  is 
that  part  which  is  driven  off  during  the  drying  period  up  to  the  time  when 
shrinkage  ceases;  and  the  “Pore  Water”  or  that  portion  which  still  remains 
when  shrinkage  ceases,  retained  in  the  pores  of  the  piece  until  the  completion 
of  the  drying  has  driven  it  all  out. 

Shrinkage  water. — The  shrinkage  water  was  determined  by  measuring 
the  volume  of  the  test  piece  before  and  after  shrinkage  ceased  and  reporting 
the  difference  in  terms  of  percentage  of  the  dry  weight ; as,  for  example : 


Percentage  of  Shrinkage  Water 


Plastic  volume 


Dry  weight 


Dry  volume 

- X 100 


Pore  water. — Since  the  pore  water  is  the  portion  of  the  water  of  plas- 
ticity retained  in  the  pores  after  shrinkage  ceases,  it  is  therefore  calculated 
as  follows : 


Percentage  of  Pore  Water  = Percentage  of  Water  of  Plasticity  — Percentage  of 

Shrinkage  Water 

Clays  in  which  the  ratio  of  shrinkage  water  to  the  pore  water  is  high 
are  likely  to  have  excessive  or  sticky  plasticity  and  to  warp  or  crack  in  drying. 
This  ratio  undoubtedly  bears  an  important  relation  to  the  strength  of  the 
unburned  clay.  These  properties  are  dependent  also  upon  other  factors  such 
as  the  shape  and  the  relative  proportion  of  the  various  sizes  of  non-plastics 
in  the  mass  so  that  in  our  present  state  of  knowledge  a correlation  cannot 

iKinnison,  C.  S.  A study  of  the  Atterberg  plasticity  method  : U.  S.  Bureau  of  Stan  1- 
ards  Tech.  Paper  No.  46,  pp.  11-12,  1915. 

2No  account  is  taken  here  of  the  hygroscopic  water,  imbibed  or  absorbed  water. 


24 


ILLINOIS  LIKE  CLAYS 


be  made.  However,  according  to  certain  investigations  by  A.  V.  Bleiningcr1 
the  best  clays  for  glass  pots  and  crucibles  have  a pore  water-shrinkage  ratio 
of  1:1. 


FINENESS 


The  relative  proportions  of  the  non-plastic  material  of  various  sizes 
present  in  clays  varies  within  wide  limits  and  the  choice  of  a clay  for  special 
purposes  sometimes  depends  upon  a particular  amount  or  size.  For  example, 
the  use  of  siliceous  clays  in  the  mixture  for  glass  pots  has  been  found  of 
distinct  advantage. 

It  is  desirable,  therefore,  to  have  such  information  available  and  it 
would  be  of  advantage  to  have  more  information  about  the  mineral  char- 
acter and  the  physical  form  of  the  non-plastic  particles. 

Plasticity,  drying  conduct,  drying  shrinkage,  strength  and  burning  prop- 
erties are  all  largely  influenced  by  the  non-plastics.  In  some  cases  the 
removal  of  non-plastics  above  a certain  size  is  necessary  as  in  the  case  of 
the  manufacture  of  stoneware. 

One  hundred  grams  of  the  dried  sample  were  shaken  with  800  cc.  of 
water  in  a mechanical  shaker  until  the  mass  was  thoroughly  disintegrated. 
The  mixture  was  then  poured  on  to  a set  of  sieves  of  the  meshes  recorded 
in  the  tests.  The  soft  lumps  of  the  residues  were  crushed  by  rubbing  with 
the  fingers  and  washed  thoroughly,  dried  and  weighed.  The  results  are 
reported  in  the  terms  of  the  total  weight  of  the  dry  clay  used. 

In  the  reports  on  the  results  of  tests  which  follow,  the  classification 
given  herewith  is  used : 


Amount  of  residue 
Per  cent 

0—3.5  

3.6—  5.5  

5.6— 10.5  .... 

10.6—25.5  .... 

More  than  25.5  . . . . 


Slight 

Low 

. . . Moderate 
Considerable 
High 


SLAKING 

The  slaking  test  has  been  recommended  as  preliminary  test  of  especial 
service  in  distinguishing  between  clays  of  high  and  low  strength.  Many 
clays  which  require  thirty  minutes  or  more  to  slake  have  high  tensile  and 
transverse  breaking  strength  in  the  unburned  condition.  Clays  which  slake 
quickly  have  low  or  medium  strength.  This  test  is  useful  for  a rough 
approximation  only  which  should  be  confirmed  by  the  usual  strength  tests. 

An  intimate  mixture  of  equal  parts  of  dry  clay  and  potter’s  flint  was 
moistened  with  water  and  after  working  to  a plastic  condition  was  shaped 
as  a bar  measuring  4 in.  by  1 in.  by  1 in.  This  bar  was  cut  into  cubes 

iBleininger,  A.  V.,  Properties  of  American  bond  clays,  etc. : U.  S.  Bureau  of  Standards 
Tech.  Paper  No.  144,  p.  51,  1920. 


METHODS  OF  TESTING 


25 


approximately  one  inch  on  each  side.  After  carefully  drying  these,  first 
at  room  temperature,  then  at  160° -170°  F.,  and  finally  at  212°  F.,  they  were 
cooled,  placed  on  wire  mesh  trays  (four  meshes  to  the  inch),  and  then 
submerged  in  water  at  room  temperature.  The  cubes  slaked  more  or  less 
slowly  and  the  time  required  for  this  to  be  completed  was  noted.  Care  was 
taken  to  avoid  agitation  of  the  water  during  the  slaking  process. 


TRANSVERSE  STRENGTH 


The  strength  of  dried  unburned  clay  is  determined  either  in  terms  of 
tensile  strength  or  the  cross-breaking  strength.  The  latter  is  more  commonly 
used  by  American  ceramists  at  present  because  of  the  simplicity  of  the 
apparatus  and  the  greater  uniformity  of  results  obtained.  A modulus  of 
rupture  of  less  than  200  pounds  per  square  inch  may  be  regarded  as  low ; 
between  200  and  400  pounds  per  square  inch  as  good ; and  above  400  pounds 
as  high.  This  test  is  of  use  in  the  valuation  of  all  clays  but  especially  those 
which  are  be  used  alone  or  with  other  clays,  and  without  the  addition  of 
non-plastics  as  such.  The  washing  of  the  clay  may  or  may  not  impair  its 
strength. 

Test  bars  6 in.  by  1 in.  by  1 in.  were  formed  according  to  the  methods 
previously  described,  dried  first  at  room  temperature,  then  at  140°  to  150°  F. 
for  24  hours,  and  finally  at  212°  to  220°  F.  for  24  hours.  After  removal 
from  the  oven,  and  cooling  to  room  temperature,  the  pieces  were  then  sup- 
ported upon  knife  edges  placed  five  inches  apart.  At  a point  midway 
between  the  supports  rested  the  knife  edge  of  a yoke  from  which  hung  a 
pail.  A stream  of  sand  was  fed  into  this  pail  until  the  weight  was  sufficient 
to  break  the  bar. 

The  result  of  the  test  was  recorded  as  the  modulus  of  rupture  which 
was  calculated  as  follows : 


Modulus  of  Rupture  i| 


3 X Weight  in  pounds  X Distance  between  supports 
2 X Breadth  X Depth2 


Twenty  pieces  were  tested  in  all  cases  where  sufficient  material  was  at 
hand.  The  final  result  reported  was  the  average  of  all  the  values  which  did 
not  vary  more  than  25  per  cent  of  the  maximum. 

The  “modulus  of  rupture”  classification  used  in  describing  the  results  of 
tests  of  transverse  strength  is  the  same  as  that  given  below  for  bonding 
strength. 


BONDING  STRENGTH 

It  is  the  practice  in  the  manufacture  of  many  kinds  of  wares  to  use 
more  or  less  non-plastic  material  containing  particles  of  varying  size  and 
shape,  as,  for  example,  in  furnace  blocks,  fire  brick,  crucibles,  glass  pots, 
abrasive  wheels,  architectural  terra  cotta,  and  zinc  retorts.  For  such  uses, 
it  is  highly  important  that  the  clays  used  should  permit  such  admixtures 


26 


ILLINOIS  FIRE  CLAYS 


with  a retention  of  maximum  strength.  Ordinarily  the  addition  of  consid- 
erable amounts  of  non-plastics  results  in  a decrease  in  the  cross-breaking 
strength  as  compared  with  that  of  the  pure  clay.  In  some  instances  there 
is  little  change  and  sometimes  an  increase.  The  following  classification  pro- 
posed by  Professor  A.  S.  Watts,1  slightly  modified,  has  been  employed : 

Modulus  of  Rupture 

Lbs.  per  sq.  in. 

Low  0—100 

Medium  Low  101 — 200 

Medium  201 — 400 

Medium  High  401 — 800 
High  801  and  above 

Equal  parts  of  clay  and  standard  sand2  were  brought  to  a plastic  condi- 
tion by  the  addition  of  water  and  thorough  wedging.  Test  pieces  were  formed 
from  this  mixture.  The  method  of  preparation,  the  size,  the  conditions  of 
drying  and  mode  of  breaking  were  similar  to  those  described  under  “Trans- 
verse Strength.” 

The  results  are  reported  in  terms  of  the  modulus  of  rupture,  which  is 
calculated  in  the  manner  already  described. 

BURNED  CLAYS  I THEIR  PROPERTIES  AND  METHODS  OF  TESTING 
PYROMETRIC  METHODS  USED 

The  test  pieces  prepared  for  the  determination  of  the  drying  shrinkage 
were  burned  in  a coal-fired  laboratory  test  kiln  of  the  down  draft  type, 
having  a chamber  capacity  of  approximately  27  cubic  feet.  The  normal 
rate  of  firing  was : 


From  room  temperature  to  572°  F 9 hours 

From  572°  F.  to  1112°  F 6 hours 

From  1112°  F.  to  1382°  F 12  hours 

From  1382°  F.  to  1850°  F 7 hours 

From  1850°  F.  to  finish 45° — 54°  F.  per  hour 


Ordinarily,  the  trial  pieces  were  placed  in  closed  saggars  to  protect 
them  from  the  flames  and  dust  carried  by  the  draught  through  the  kiln. 

A separate  burn  was  made  for  each  of  the  several  pyrometric  cones 
indicated  in  the  reports  on  the  tests,  excepting  as  it  became  desirable  in 
some  cases  to  set  the  kiln  so  that  test  pieces  could  be  drawn  from  time  to 
time  as  the  desired  cone-temperature  was  reached. 

iWatts,  A.  S.,  Classification  of  clays  on  a ceramic  basis : Jour.  Am.  Cer.  Soc.  Vol. 
3,  p.  247,  1920. 

"Standard  sand  is  prepared  especially  for  use  in  the  testing  of  cement.  It  is  sized  to 
pass  a twenty-mesh  sieve  (0.0328-inch  hole,  0.0172-inch  wire)  and  is  retained  on  a twenty- 
eight  mesh  (0.0232-inch  hole,  0.0125-inch  wire). 


METHODS  OF  TESTING 


27 


The  pyrometric  cones  used  were  those  made  by  Professor  Edward 
Orton,  Jr.,  of  Columbus,  Ohio.  With  respect  to  the  temperature  equivalents 
of  these  cones,  it  should  be  borne  in  mind  that  the  pyrometric  cone  is  a 
measure  of  the  effect  of  the  time-temperature  relation  as  has  been  repeatedly 
pointed  out  but  often  disregarded.  Therefore,  the  temperature  at  which  a 
cone  “goes  down”  is  dependent  upon  the  rate  of  firing.  This  has  been 
carefully  investigated  by  the  Bureau  of  Standards  and  is  discussed  in  a 
paper  on  “The  Function  of  Time  in  the  Vitrification  of  Clays,”  published 
as  Technologic  Paper  No.  17.  In  the  following  table,  a comparison  is  made 
of  the  cone-temperature  scale:  Scale  (a)  is  as  usually  given,  and  scale  (b) 
is  as  reported  in  the  paper  referred  to  when  the  rate  of  heating  was  at  49.5° 
F.  per  hour,  which  is  nearly  that  used  in  these  burns. 


COMPARISON  OF  TWO  CONE-TEMPERATURE  SCALES 


(a) 

(b) 

Cone 

Usual  Scale 

Rate  = 

27V2°  C. 

per 

hour 

Deg.  F. 

Deg.  C. 

Deg.  F. 

010 

1742 

885 

1625 

09 

1778 

930 

1706 

08 

1814 

970 

1778 

07 

1850 

975 

1787 

06 

1886 

1000 

1832 

05 

1922 

1035 

1895 

04 

1958 

1055 

1931 

03 

1994 

1065 

1949 

02 

2030 

1070 

1958 

01 

2066 

1080 

1976 

1 

2102 

1085 

1985 

2 

2138 

1090 

1994 

3 

2174 

1110 

2030 

4 

2210 

1125 

2057 

5 

2246 

1135 

2075 

6 

2282 

1140 

2084 

7 

2318 

1155 

2111 

8 

2354 

1170 

2138 

9 

2359 

1190 

2174 

A thermo-electric  pyrometer  was  used  in  each  burn  in  order  to  determine 
the  rate  of  increase  of  temperature.  It  was  thought  impracticable  to  rely 
solely  upon  the  pyrometer  in  finishing  the  burns  because  of  the  impossibility 
of  grouping  the  test  pieces  within  or  without  the  saggars  close  enough  to 
the  thermocouple  to  insure  certainty  regarding  the  uniformity  of  the  tem- 
perature distribution,  whereas  the  cones  could  be  scattered  throughout  the 
kiln  where  needed. 

Two  pieces  were  burned  at  each  temperature  indicated  in  practically 
every  case,  and  an  average  taken  of  the  results  obtained. 


28 


ILLINOIS  FIRE  CLAYS 


A 

B 

C 

D 

E 

F 

G 

H 

J 

K 

L 

M 


6-inch  wrought  iron  pipe 
Cap 

Machined  flange 
Glass  desicator  cover 
J4-inch  pipe 
Outlet  pipe  with  cap 
Rubber  pressure  tubing 
Glass  T 

Mercury  vacuum  gauge 
Level  of  water 
Briquets 

Pipe  to  vacuum  pump 


Fig.  45.  Apparatus  for  saturating  briquets  in  vacuo. 


METHODS  OF  TESTING 


29 


BURNING  SHRINKAGE 

The  shrinkage  resulting  from  burning  is  the  contraction  due  to  the  loss 
of  water  and  other  volatile  matter,  a certain  amount  of  condensation  of 
the  components,  and  the  softening  of  the  mass  with  the  consequent  closing 
up  of  the  voids  by  the  more  fluid  portions.  A high  shrinkage  may  lead  to 
cracking  or  warping  of  the  piece  and  is  avoided  therefore  in  the  manufacture 
of  all  ware  of  complicated  form  or  large  size.  The  following  classification 
proposed  by  Professor  A.  S.  Watts,  slightly  modified,  is  presented  for  com- 
parison : 

Total  Shrinkage  at  Cone  10 
Per  cent 
Low  0 — 4 

Medium  Low  4.1 — S 
Medium  8.1 — 12 

Medium  High  12.1 — 16 
High  16  and  above 

In  the  “Results  of  tests”  included  in  this  report,  the  term  “Burning 
shrinkage”  means  linear  burning  shrinkage  in  every  case. 


POROSITY 


Porosity  is  the  ratio  between  the  volume  of  the  pores  and  the  volume 
of  the  whole  piece.  The  volume  of  the  pores  was  determined  by  saturating 
the  piece  with  water  in  vacuo  (see  Fig.  45)  and  noting  the  weight  of  the 
water  absorbed.  The  volume  of  the  piece  thus  saturated  was  obtained  by 
measuring  the  amount  of  displacement  caused  by  its  introduction  into  a modi- 
fied form  of  the  Seger  volumeter.  This  apparatus  consists  of  a large-size 
glass  bottle  with  a wide  neck  covered  by  a glass  cap  ground  to  fit  snugly. 
To  the  side  of  this  bottle  is  connected  a burrette  or  graduated  glass  tube, 
which  permits  a reading  of  any  change  of  volume  of  the  contents  of  the 
large  bottle.  The  per  cent  porosity  is  calculated  as  follows : 


Saturated  weight  — dry  weight  =:  weight  of  water  absorbed 
Weight  of  water  absorbed  gives  volume  of  water  absorbed 
Volume  of  water  absorbed  ^volume  of  pores 
Volume  of  pores 

r— — - ■ r X 100  = Percentage  of  Porosity 

Volume  of  test  piece  (including  pores) 


COLOR 

The  color  changes  at  the  various  cones  were  noted. 

FUSION,  OR  DEFORMATION  TESTS 

The  fusion  or  deformation  tests  were  made  in  a Fletcher  furnace  for 
the  lower  temperatures  and  in  a Deville  furnace  for  the  more  refractory 
materials.  The  latter  is  operated  by  placing  the  test  pieces  in  a crucible, 
surrounding  them  with  coke,  and  forcing  the  combustion  with  a low  pres- 


30 


ILLINOIS  FIRE  CLAYS 


sure  air  blast.  The  test  pieces  were  molded  into  the  form  of  four-sided 
pyramids  measuring  0.23  inches  along  each  edge  of  the  base  and  1.2  inches 
high.  Standard  pyrometric  cones  made  by  Professor  Edward  Orton,  Jr., 
were  placed  in  the  furnace  with  the  test  pieces  to  serve  as  indicators  of 
the  cone  temperatures  reached. 

In  the  reports  of  the  results  of  tests,  clays  which  deform  below  cone  27 
are  termed  non-refractory,  those  which  deform  between  cones  27  and  31  in- 
clusive, refractory,  and  those  which  deform  at  cone  33  and  above,  highly 
refractory. 

DISTRIBUTION  OF  ILLINOIS  CLAYS 

By  C.  R.  Schroyer 

Refractory  clay  is  restricted  in  Illinois  to  the  basal  part  of  the  Pennsyl- 
vanian (“Upper  Coal  Measures”)  and  to  the  younger  embayment  deposits 
of  Cretaceous-Tertiary  age.  A few  local  developments  are  associated  with 
other  horizons,  usually  as  residuals  above  limestones,  but  such  occurrences 
are  rare  and  not  of  great  importance.  The  clays  will  be  discussed  in  order, 
as:  (1)  Clays  of  the  embayment  area,  (2)  Clays  of  Pennsylvanian  age. 

Geographically  the  refractory  clays  of  Illinois  are  to  be  found  (1)  in  the 
extreme  southern  counties;  (2)  in  a narrow  zone  extending  from  East  St. 
Louis  to  Rock  Island;  and  (3)  locally  along  Illinois  River  in  LaSalle  and 
Grundy  counties.  Fig.  43  indicates  the  general  distribution  of  refractory 
clays. 

The  southern  clays  are  part  of  the  younger  embayment  deposits  and 
are  found  in  Pope,  Massac,  Pulaski,  Alexander,  Union,  and  Johnson  coun- 
ties. The  “pocket”  deposits  near  Mountain  Glen,  Union  County,  are  the 
most  important  and  have  furnished  the  highest  grade  clay.  Others  of  a 
similar  nature  are  found  near  Grand  Chain,  Pulaski  County.  In  the  counties 
adjoining  Ohio  River,  bedded  clay  is  widely  distributed  but  is  not  always 
of  a quality  desirable  for  commercial  purposes.  Figure  46  shows  the  em- 
bayment deposits. 

The  zone  extending  from  East  St.  Louis  to  Rock  Island  (see  Fig.  43) 
includes  parts  of  St.  Clair,  Madison,  Calhoun,  Greene,  Pike,  Scott,  Adams, 
Brown,  Schuyler,  McDonough,  Fulton,  Warren,  Mercer,  Rock  Island,  and 
Henry  counties.  While  clay  is  quite  generally  present  at  the  Cheltenham 
horizon  throughout  this  entire  belt,  it  is  only  locally  of  commercial  value, 
as  at  Alton,  Madison  County,  Alsey,  Scott  County,  Colchester  and  Macomb, 
McDonough  County,  and  Rock  Island,  Rock  Island  County. 

In  La  Salle  and  Grundy  counties  at  the  base  of  the  Pennsylvanian 
there  is  also  a clay  of  refractory  value.  Pits  are  worked  near  Utica  and 
Ottawa,  and  mines  near  Oglesby  and  Marseilles.  In  the  vicinity  of  Goose 
Lake,  Grundy  County,  there  is  a partially  developed  deposit  which  contains 
lenses  of  a semi-flint  type  of  clay. 


THE  EMBAYMENT  CLAYS 


31 


A report  by  Stuart  St.  Clair  gives  in  some  detail  a discussion  of  the 
Union  County  clays.1  E.  H.  Lines  has  studied  the  stratigraphy  of  the  Chelt- 
enham clay  of  Illinois.2  As  those  publications  are  still  available,  only  such 
of  the  matter  of  those  reports  will  be  repeated  as  is  necessary  for  clearness. 

In  the  introduction  a general  discussion  has  been  made  of  the  classifi- 
cation of  clays,  their  properties  and  uses,  and  methods  of  testing.  For  a 
discussion  of  the  character  and  origin  of  clays,  the  reader  is  referred  to 
Bulletin  93  of  the  Survey. 

CLAYS  OF  THE  EMBAYMENT  AREA 

Long  after  the  Pennsylvanian  (“Coal  Measures”)  shales,  limestones, 
sandstones,  and  coals  had  been  deposited,  and  after  the  surface  of  these 
formations  had  been  weathered  and  eroded,  the  level  of  the  sea  relative  to 
the  land  changed  so  that  a wide  open  bay  extended  from  the  Gulf  of  Mexico 
northward  into  southern  Illinois.  Debris  carried  into  this  basin  from  the 
bordering  land  formed  interstratified  beds  of  sand,  silt  and  clay,  which  make 
up  the  embayment  deposits  (see  fig.  46)  and  include  the  refractory  clays  of 
southern  Illinois. 

Paleozoic  Floor  and  Border 

Beds  of  Paleozoic  age  border  the  embayment  deposits  on  the  outer  rim 
and  presumably  form  the  floor  of  the  entire  basin.  Their  decayed  products 
have  been  the  source  of  the  younger  sediments.  In  Illinois  these  Paleozoic 
rocks  are  of  Mississippian  and  Devonian  age.  The  Mississippian  beds 
forming  most  of  the  eastern  and  northern  border  are  cherty  limestone  and 
shale  with  minor  horizons  of  sandstone.  The  high  bluff  of  a former  channel 
of  Ohio  River  roughly  parallels  embayment  deposits  on  the  north  and  rises 
at  New  Columbia  to  a height  of  150  feet  above  them.  Erosion  has  exposed 
Mississippian  beds  in  southwestern  Pope,  central  Massac,  and  Pulaski  coun- 
ties south  of  this  channel,  either  as  highland  inkers  or  as  bordering  fringes 
at  the  north  of  the  embayment  deposits. 

In  Alexander  and  Union  counties  older  beds  of  Devonian  age  border 
the  embayment  area  and  form  the  highlands  of  southwestern  Illinois.  These 
cherts  and  decayed  siliceous  rocks  overlie  Alexandrian  and  Ordovician  lime- 
stones which  outcrop  in  the  bluffs  of  the  Mississippi  River  flood-plain. 

Correlation  and  Division  of  the  Embayment  Deposits 

From  certain  features  common  to  the  embayment  deposits  and  other  beds 
elsewhere,  and  from  the  continuity  of  connection  at  the  south  as  well  as 
from  an  occasional  fossil,  these  beds  are  known  to  be  of  Cretaceous  and 

JSt.  Clair,  Stuart,  Clay  deposits  near  Mountain  Glen,  Union  County,  Illinois:  111. 
State  Geol.  Survey  Bull.  36,  pp.  71-83,  1920. 

2Lines,  Edwin  H.,  Pennsylvanian  fireclays  of  Illinois : 111.  State  Geol.  Survey  Bull. 

30,  pp.  61-73,  1917. 

3Rolfe.  C.  W.,  Geology  of  clays  (part  of  paving  brick  and  paving  brick  clays  of 

Illinois)  : 111.  State  Geol.  Survey  Bull.  9,  pp.  1-46,  1908. 


32 


ILLINOIS  FIRE  CLAYS 


swings  north  from  Arkansas  into  Illinois  and  thence  south  into  Alabama,  is  the 
boundary  of  the  deposits  laid  down  in  the  embayment  which  extended  northward 
from  the  Gulf  in  Cretaceous  and  Tertiary  times.  Only  the  outcrop  of  the 
Ripley  formation  is  shown.  South  of  the  Ripley  in  Illinois  Eocene  and 
younger  formations  are  uppermost,  and  remnants  of  these  younger 
formations  are  found  even  in  and  perhaps  beyond  the  area 
mapped  as  Ripley.  (After  Stephenson.) 


THE  EMBAYMENT  CLAYS 


33 


Tertiary  age.  In  the  states  farther  south,  where  there  are  definite  breaks 
between  formations,  it  has  been  possible  to  draw  lines  that  definitly  sub- 
divide these  deposits,  as  indicated  in  the  accompanying  table.  In  Illinois, 
however,  with  only  the  outer  margins  present  it  is  difficult  and  in  some  cases 
probably  impossible  to  separate  them  into  distinct  horizons. 

Each  formation  listed  in  Table  1 represents  a transgression  of  the  sea 
and  each  break  represents  a period  of  erosion.  How  far  north  these  beds 
extended  or  how  thick  they  were  originally  can  not  be  determined  from  their 
present  distribution.  Small  outliers  are  found  far  beyond  the  areas  of  con- 
nected strata.  For  example,  at  New  Columbia,  Massac  County,  and  south 
along  the  bluff  such  remnants  are  found  both  as  terraces  and  as  thin  beds 
over  the  Paleozoic  uplands,  150  feet  or  more  above  the  present  valley  level, 
as  indicated  by  the  fact  that  a well  on  the  bluff  southeast  of  New  Columbia 
18  feet  deep  ended  in  red  sand  by  a section  of  the  road  from  the  levee  to 
the  top  of  the  bluff  at  this  place : 

Section  of  bluff  at  New  Columbia 


Thickness 
Ft.  In. 

9.  Loess  10 

8.  Gravel 6 

7.  Sandstone,  platy,  red  and  gray 6 6 

6.  Sandy  beds,  light  in  color 10  8 

5.  Sandstone,  shaly;  weathers  to  3-inch  beds 6 

4.  Clay  shales,  sandy,  white  and  buff  interbedded 7 6 

3.  Clay,  sandy,  white  with  iron-colored  streaks 3 

2.  Partly  covered 5 

1.  Sandstone  (Mississippian)  100  (Bar.) 


A section  measured  near  Rosebud  gives  similar  indications : 

Section  2 miles  south  of  Rosebud,  Pope  County, 
in  the  SE.  Y sec.  33,  T.  14  S.,  R.  6 E. 

Thickness 

Feet 


6.  Gravel  2± 

5.  Clay,  light  colored,  sandy,  and  thin  beds  cemented  by  iron 16 

4.  Shales,  buff  and  gray,  sandy;  thin  compact  irony  beds  near  the  top.  6Yz 

3.  Sandy  beds,  partly  covered,  variegated,  micaceous 22 

2.  Covered 40  (Bar.) 

1.  Limestone  (Mississippian)  25 


This  bluff  rises  150  feet  above  the  level  of  the  present  alluvial  deposits 
and  the  capping  suggests  that  it  has  been  completely  buried  by  a filling  of 
sand  and  clay. 

Near  Vienna,  Johnson  County,  small  terrace  remnants  of  bluish  white 
stratified  clay  shale  interbedded  with  hard  red,  sandy  beds  also  suggests 
the  former  presence  of  more  extensive  deposits.  Such  small  remnants  are 


34 


ILLINOIS  FIRE  CLAYS 


Table  1.  Subdivisions  of  the  embayment  deposits,  recognized  by  various  authors 


Description  of  Horizon 

Approx- 

imate 

Thickness 

From 

Professional  Papers  a 

81,  90 J.  95F, 

120C,  and  120H 

From 
Water- 
Supply 
Paper 164b 

System 

Relations 

In  Illinois 

Sands  with  clay  lenses  and  green- 
sand. Characteristic  life  remains 

Feet 

200 ± 

Formations 

Jackson 

Formations 

Tertiary  (Eocene) 

Not  repre- 
sented in  Illi- 
nois 

Highly  fossiliferous  greensands 
not  recognized  outside  of  the 
Alabama  area 

30  to  40 

Gosport 

Claiborne 

450± 

nterval) 

Lagrange 

Calcareous,  argillaceous,  and 

glauconitic  fossiliferous  sands 

100  to  150 

Lisbon 

Siliceous  claystone,  calcareous  and 
fossiliferous  toward  the  east 

200 ± 

Tallahatta 
(Erosion  i 

Hatchetigbee 

Laminated,  sandy  clays  and  cross- 
bedded,  calcareous  sands  carry- 
ing fossils  and  some  greensand 

175 

Wilcox 
850 ± 

Represented 
in  Illinois. 
The  high 
grade  clays  of 
Mountain 
Glen,  Grand 
Chain  and 
possibly 
Raum,  ques- 
tionably re- 
ferred to  this 
horizon.  Con- 
tinuous de- 
posits cover  a 
triangular 
area  in  the 
extreme  sou- 
thern part  of 
State 

Sandy  clays  and  thick  lenses  of  cal- 
careous glauconitic  sands.  A 
bed  of  lignite  at  the  base 

? 

i 

Bashi 

l 

Gray  and  yellowish  cross-bedded 
sands  and  sandy  clays,  massive 
below  and  laminated  above 

140 

1 

\ 

Tuscahoma 

1 

Sandy  glauconitic  beds  alternating 
with  grayish,  calcareous  clays. 
Lignite  bed  at  base 

200 

1 

i 

Nanafalia  | 

J 

(Erosion  ii 

Naheola  1 

Sucarnochee  J 

Clayton 

iterval) 

Lignitic  ferruginous  sandy  clays 
and  beds  of  lignite  or  coarse 
micaceous,  highly  colored  sands 
with  micaceous  clays.  Green- 
sand 

? 

Midway 

Porters 

Creek 

Probably  pres- 
sent,  but  no 
distinctive 
marks  of 
identification 

Sands  usually  light  in  color,  but 
with  considerable  variation;  pink 
light  yellowish,  brown,  and  local- 
ly also  leaden  or  slate  colored 
clay,  10  to  20  or  more  feet  thick. 
Iron  concretions  characteristic. 
Calcareous  and  glauconitic  beds 

250  to  300 

CIU31U11  UllCl  vai 

and  faunal  change) 

(Thought  to  be  of  the  same 
age  as  the  Selma  farther 
south) 

< 

Ripley 
(McNairy 
sand  mem- 
ber at  the 
north) 

Cretaceous 

Extends  as  a 
curved  belt  5 
to  15  miles 
wide  about 
the  outer 
margin  of  the 
embayment 
deposits. 
Known  from 
deep  excava- 
tion at  Cairo 

Clay  of  a light  leaden  gray  or  green- 
ish color  when  dry:  somewhat 
darker  when  wet.  Greensand 
present  in  some  layers.  Calcar- 
eous shells  at  the  south 

950 

Selma 

Absent 

Sands  which  locally  contain  calcium 
carbonate  and  greensand 

450 

Eutaw 

Sands  and  clays  of  shallow  water 
origin 

1000± 

Tuscaloosa! 

(Distinct  break) 

Paleozoic  formations 

“-Stephenson,  L.  W.,  Cretaceous  deposits  of  the  eastern  Gulf  region:  U.  S.  Geol.  Survey  Prof.  Paper 
81,  1914. 

Stephenson,  L.  W.,  The  Cretaceous-Eocene  contact  in  the  Atlantic  and  Gulf  coastal  plain:  U.  S.  Geol. 
Survey  Prof.  Paper  90J,  1915. 

Berry,  E.  W.,  Erosion  intervals  in  the  Eocene  of  the  Mississippi  embayment:  U.  S.  Geol.  Survey  Prof. 
Paper  95F,  1915. 

Cooke,  C.  W.,  and  Shearer,  H.  K.,  Deposits  of  Claiborne  and  Jackson  age  in  Georgia:  U.  S.  Geol.  Survey 
Prof.  Paper  120C,  1918. 

Stephenson,  L.  W.,  A contribution  to  the  geology  of  northeastern  Texas  and  southern  Oklahoma:  U.  S. 
Geol.  Survey  Prof.  Paper  120H,  1918. 

b-Glenn,  L.  C.,  Underground  waters  of  Tennessee  and  Kentucky  west  of  Tennessee  River  and  of  an 
adjacent  area  in  Illinois:  U.  S.  Geol.  Survey  Water-Supply  and  Irrigation  Paper  No.  164,  1906. 


THE  EMBAYMENT  CLAYS 


35 


known  in  the  Devonian  area  of  Alexander  and  Union  counties  as  far  north 
as  Mountain  Glen,  and  the  deposits  of  refractory  clay  at  that  place  are  prob- 
ably outliers.  Still  farther  north  clay  has  been  dug  at  an  elevation  of  about 
625  feet  above  sea  level,  northwest  of  Alto  Pass  near  the  north  line  of  Union 
County.  Outliers  of  sand  and  thin-bedded  clays  are  found  west  of  Pomona 
in  Jackson  County  at  an  elevation  of  about  650  feet  above  sea  level.  This 
clay  is  so  white  that  it  has  been  used  by  the  farmers  for  white  wash  and  paint. 


CRETACEOUS  SYSTEM 
UPPER  CRETACEOUS  SERIES 
RIPI.EY  FORMATION 

The  four  lower  embayment  formations  listed  in  the  table  are  of  Cre- 
taceous age  but  only  the  highest  of  these,  the  Ripley  formation,  extends  into 
Illinois.  The  northern  extension  of  this  formation  is  composed  largely  of 
loose  sands  and  sandstone,  and  is  known  as  the  McNairy  sand  member.  The 
McNairy  extends  in  a curved  belt  across  southwestern  Pope,  southern  Mas- 
sac, and  central  Pulaski  counties,  and  in  a constricted  narrow  belt  across 
Alexander  County,  terminating  not  far  from  Fayville  at  Mississippi  River. 
The  width  of  this  belt  varies  from  10  miles  north  of  Metropolis  to  less  than 
half  that  width  in  central  Alexander  County.  Younger  beds  of  Tertiary 
and  Quaternary  age  overlie  most  of  this  area. 

Lithologic  Character. — In  Tennessee  the  Ripley  formation  is  composed 
mostly  of  stratified,  variegated  sands,  that  are  commonly  rich  in  iron  and 
contain  “pipes”  and  irony  masses.  “The  sands  are  usually  fine  gravel  and 
between  them  are  found  beds  of  gray  lignite  or  yellow  sandy  micaceous 
clay.”1  Drying  cracks  now  filled  with  limonite  indicate  periods  of  exposure 
early  in  the  history  of  the  deposit. 

In  Kentucky  the  Ripley  is  a “black  clay  in  very  thin  laminae,  separated 
by  fine  white  and  highly  micaceous  sand ; beds  of  sharp  angular  white  and 
yellow  micaceous  sand  100  feet  thick.”2 

In  Illinois  the  fewness  of  Ripley  exposures  makes  study  of  this  horizon 
difficult.  In  general,  however,  the  formation  is  made  up  of  variegated 
sands  interstratified  with  beds  of  gray,  leaden,  or  slate-colored  clay,  10  to 
20  feet  or  more  thick.  The  sands  are  commonly  rich  in  iron,  and  ironstone 
layers  and  concretionary  masses  are  abundant.  The  clays  of  Massac  County 
are  of  this  age. 

Sections  of  the  McNairy  sands  of  the  Ripley  formation  in  Illinois 
follow : 


iNelson,  W.  A.,  Clay  deposits  of  West  Tennessee : Geol.  Survey  of  Tennessee  Bull. 
5,  p.  li,  1911. 

2Gardner,  James  H.,  Kentucky  Geol.  Survey  Bull.  6,  p.  S3,  1905. 


36 


ILLINOIS  FIRE  CLAYS 


Log  of  the  Eichcnseer  well,  one  mile  below  Yates  Landing  in  the 
SW.  % sec.  2,  T.  15  S.,  R.  2 E. 


Thickness  Depth 
Feet  Feet 

Description  of  strata 

Loam  and  loess  18  18 

Gravel,  coarse  3 21 

Sand,  white  30  51 

“Potters  clay,”  white  6=*=  57 

Sand,  white,  with  small  lumps  of  clay 70  127 

Section  of  east  bank  of  drainage  ditch  300  yards  north  of  Ohio  River 

Thickness 
Ft.  In. 

5.  Soil  1 3 

4.  Loess  5 to  15 

3.  Gravel  and  sand,  stained  brown  or  red  by  iron ; compact  at 

base 1 3 

2.  Clay,  bluish,  micaceous,  sandy,  with  thin  lenses  of  sand 2 6 

1.  Sand  and  clay  interbedded  and  slumped  together 8 10 

Log  of  the  Stoner  zvell  in  sec.  28,  T.  15  S.,  R.  6 E. 


Thickness 

Depth 

Description  of  strata 

Feet 

Feet 

Clay  and  “loam,”  yellow  

10 

10 

Sand,  fine 

2V2 

1 2V* 

“Soapstone,”  dark  compact  clay, 

with  lignite 9 

21 H 

Sand  and  clay,  red  in  color ; some 

harder  irony  layers,  others  white 

and  buff  

28 

49^4 

Rock,  hard  ; bottom  of  well 


Section  half  a mile  west  of  Round  Knob 

Thickness 
Ft.  In. 


4.  Gravel ; unmeasured 

3.  Clay,  red  4 

2.  Clay,  white  and  pink  6 6 

1.  Sand,  red  and  white,  case  hardened  ferruginous  layers 18 


TERTIARY  SYSTEM 
EOCENE  SERIES 
MIDWAY  FORMATION 

The  Midway  formation  includes  the  oldest  beds  of  Tertiary  age,  and 
south  of  Illinois  it  rests  with  marked  unconformity  on  the  underlying  Cre- 
taceous. 

Only  in  the  vicinity  of  Caledonia  Landing  east  of  Olmsted  have  exposed 
deposits  in  Illinois  been  correlated  with  the  Midway,  although  in  wells  at 


THE  EMBAYMENT  CLAYS 


37 


Cairo  and  Mound  City,  beds  100  feet  thick  have  been  classified  as  Porters 
Creek  [Midway].1 

This  phase  of  the  Midway  extends  westward  from  Caledonia  as  a belt 
a few  miles  wide. 

Lithologic  Character. — Sections  indicating  the  character  of  the  Midway, 
especially  its  variability,  follow  : 

Section  of  the  Midzvay  formation  at  Caledonia  Landing 2 

Thickness 

Feet 


8.  Gravel,  sand,  and  shale  fragments 5 

7.  Shale  fragments,  light  gray;  probably  “in  place” 25 

6.  Shale,  light  gray,  lumpy  11 

5.  Clay,  sandy,  greenish  gray  and  seamed  by  ferruginous  clay  “dike” 1 

4.  Clay  shale,  dark  gray  or  drab,  seamed  by  ferruginous  clay  “dike” 6 

3.  Shale  fragments,  light  gray  3 

2.  Clay  shale,  brown  to  black,  “fat,”  lumpy 3 

1.  Shale,  debris,  dark  and  light  gray  2 

Water  level 


The  section  varies  from  place  to  place  as  is  evident  from  the  following: 

Section  of  Midway  formation  a quarter  mile  upstream  from  Caledonia  Landing 

Thickness 
Ft.  In. 


12.  Gravel,  chert  pebbles 1± 

11.  Shale,  gray,  sandy,  small  stains  of  lignite 8 

10.  Sand,  small  hollow  iron  concretions 3 6 

9.  Sands  and  clay,  buff  and  gray,  partly  covered 5 6 

8.  Hematite  layer 2 

7.  Sand  6 

6.  Iron  oxide  bed,  concretionary,  platy 4 

5.  Sand,  gray,  micaceous  2 

4.  Ferruginous  bed  10 

3.  Sand,  buff,  and  iron  concretions 1 6 

2.  Concretionary  ferruginous  bed,  indistinct  fossil  casts  (?) 8 

1.  Covered  10  (Bar.) 

Water  level 


The  nature  of  the  Midway  beds  at  this  place  strongly  suggests  beds  of 
Ripley  age. 

Less  than  a quarter  mile  below  Caledonia  Landing,  a solid  bank  of  55 
feet  of  dark  shale,  almost  black  when  wet,  but  light  gray  when  dry,  rises 
above  the  water  level.  Upon  drying  it  cracks  out  in  characteristically  large, 
roughly  angular  blocks.  This  deposit  is  the  “soapstone”  of  the  Midway 
group. 


iPurdy,  Ross  C.,  and  DeWolf,  Frank  W.,  111.  State  Geol.  Survey  Bull.  4,  p.  143,  1907. 

2Op.  cit.,  p.  144. 


38 


ILLINOIS  FIRE  CLAYS 


Section  of  Chalk  Bank  2l/2  miles  above  Caledonia 

Thickness 
Ft.  In. 


Pleistocene  and  Recent  deposits 

11.  Soil,  grading  into  loess  at  base 1 6 

10.  Loess  15 

Lafayette  formation 

9.  Clay,  sandy  and  bedded,  below ; angular  chert  pebbles  in  clay 

above;  a re-worked  base 3 

Midway  formation 

8.  Sand  and  limonite  beds ; cross-bedded,  clayey  above,  stringers 

of  clay  pebbles  in  base 10 


7.  Sand,  very  fine,  ash-colored  ; limonite  concretions,  clay  lenses 

near  top;  “Petrified  hickory”;  wash  shows  greensand....  30 
Sharp  break 

Ripley  formation 

6.  Clay,  chocolate,  stained  by  plant  remains 6 

5.  Sand,  ash-colored  and  buff  8 

4.  Covered  5 6 

3.  Clay  3 

2.  Limonite,  concretionary  1 

1.  Clay  shale,  micaceous,  thinly  bedded,  numerous  pyrite  concre- 
tions ; several  seams  colored  dark  by  lignite  and  fragments 

of  plants  (approx.)  10 

Water  level 

This  horizon  is  replaced  but  a short  distance  below  by  clay  and  sand  in 
which  limonite  and  lignite  streaks  are  common. 

Section  in  ravine  three  quarters  mile  northwest  of  Chalk  Bank 

Thickness 

Feet 


Midway  formation 

5.  Clay  shale,  dark  10 

4.  Sand  in  loose  beds,  containing  greensand;  grades  into  clay  above..  4 

3.  Conglomerate,  rich  in  iron  oxide;  voids  filled  with  sand 1 

2.  Greensand,  as  above,  a few  quartz  pebbles ZV2 

1.  Clay  shale,  impure  3 


The  greensand  of  the  preceding  section  is  about  30  feet  higher  than 
the  base  of  the  Chalk  Bank  section  and  is  exposed  in  several  hollows  above 
Chalk  Bank.  Greensand  is  also  reported  from  near  low  water  mark  at 
Hillerman’s  Landing,  but  was  not  seen  in  place. 

Wilcox  Group 

The  Wilcox  group  includes  the  youngest  beds  of  Tertiary  age  in  Illi- 
nois. They  are  exposed  over  the  higher  areas  of  southern  Pulaski  and 
Alexander  counties.  A section  at  Fayville  of  beds  which  are  regarded  as 
belonging  to  this  horizon  is  as  follows : 


THE  EMBAYMENT  CLAYS 


39 


7. 

6. 

5. 

4. 

3. 

2. 

1. 


Section  including  the  Wilcox  group,  at  Fayville 


Soil  

Loess  

Clay  and  sand,  ash-colored 

Sand,  buff,  partially  cemented 

Conglomerate  layer  cemented  by  iron ; pebbles  up  to  3 inches  in 

diameter  

Clay,  lignitic  

Clay,  sandy,  micaceous  


Thickness 
Ft.  In. 

1 3 

10 

4 

5 6 

1 6 

3 

4 


On  the  land  of  the  Aetna  Powder  Company  other  Wilcox  deposits  are 
found : 9 feet  of  light  drab  to  gray  laminated  clay  with  partings  of  mica 

and  an  occasional  thin  seam  of  sand  is  exposed  at  the  first  separator  house ; 
and  in  the  cut  made  for  a railroad  spur  there  are  20  feet  of  loose  white  sand. 
Pits  dug  for  clay  have  penetrated  similar  sands  in  the  Mountain  Glen  dis- 
trict of  north  central  Union  County,  and  the  sand  beds  at  Hillermans  Land- 
ing and  Grand  Chain  are  also  similar.  These  facts  suggest  but  do  not  prove 
that  the  white  clays  above  the  sands  at  Mountain  Glen  and  Grand  Chain 
may  be  at  the  same  horizon  in  the  Wilcox  group.  The  distribution  and  a 
similarity  of  elevation  suggest  that  they  are  isolated  deposits  overlying  an 
irregular  erosion  surface. 


PLIOCENE  SERIES 

Certain  beds  formerly  included  in  the  Lafayette  formation  have  recently 
been  shown1  to  be  parts  of  different  deposits  and  to  belong  to  several  forma- 
tions, most  of  which  are  as  yet  unnamed.  “It  is  believed  to  be  made  up 
of  unrelated  or  distinctly  related  materials  that  * * * consist  in  the 

main  of  more  or  less  modified  parts  of  the  underlying  formations,  including 
some  residuum  and  colluvium,  and  of  terrace  deposits  of  Pliocene  and 
Quaternary  age.”2 

The  Pliocene  deposits  in  Illinois  show  evidences  of  transportation  and 
will  probably  prove  to  be  terrace  remnants.  Chert  pebbles,  angular  masses, 
and  rounded  quartz  pebbles  predominate.  Lenses  of  clay  or  of  clay  and 
sand  occur,  generally  below  the  gravel,  and  there  is  commonly  sufficient  fine 
material  to  fill  all  voids.  The  common  color  is  red.  The  pebbles  often  show 
a polish  akin  to  a desert  polish  over  a maturely  etched  surface.  Large  masses 
display  the  same  polish  as  do  small  rounded  ones. 

Huge  masses  of  conglomerate  are  included  within  other  conglomerates, 
perfect  polished  surfaces  are  a second  time  recoated  with  rough  red  iron 
cement,  features  which  are  to  be  taken  as  evidences  of  re-working,  trans- 
portation, and  redeposition. 

iShaw,  E.  W.,  The  Pliocene  history  of  northern  and  central  Mississippi : U.  S.  Geol. 
Survey  Prof.  Paper  108  H,  1918. 

2Op.  cit.,  p.  161. 


40 


ILLINOIS  FIRE  CLAYS 


These  beds  may  once  have  covered  the  older  formations  and  overlapped 
them  at  the  north.  However  that  may  be,  erosion  has  since  removed  all  but 
small  terrace  shoulders  on  the  slopes  or  isolated  remnants  over  the  higher 
areas. 

QUATERNARY  SYSTEM 
PLEISTOCENE  SERIES 
Loess  Formation 

Above  the  gravel  and  red  clay  horizon  is  a sheet  of  loess,  which  extends 
as  a mantle  over  and  beyond  the  embayment  deposits  and  except  where 
removed  by  erosion  is  everywhere  present.  It  is  composed  of  a porous,  buff, 
silty  clay  which  stands  in  vertical  walls.  In  color  it  varies  from  yellowish 
brown  to  red.  The  thickness  of  this  bed  varies  from  place  to  place,  ranging 
from  a mere  trace  to  as  much  as  forty  or  fifty  feet. 

RECENT  SERIES 
Alluvial  Deposits 

The  latest  deposits  of  this  region,  the  river  flood-plains,  form  the  prin- 
cipal surficial  covering  over  the  continuous  elongate  lowland  area  which 
extends  from  Ohio  River  above  Bay  City  westward  past  Brownfield,  New 
Columbia,  Belknap,  and  Ullin  on  the  south,  and  Temple  Hill,  Grinnell,  and 
Pulaski  on  the  north.  They  extend  from  Mound  City  west  to  near  Fay- 
ville  where  Cache  River  occupies  a part  of  this  flat  which  was  at  one  time 
the  flood-plain  of  Ohio  River.  Another  smaller  area  extends  from  below 
Hamletsburg  to  near  Brookport. 

“There  are  two  distinct  flood-plains  though  not  always  present  at  one 
locality.  The  upper  or  ‘second  bottoms’  lies  45  feet  or  more  above  low 
water,  and  has  a much  greater  extent  than  the  lower  plain,  more  recently 
developed  at  a level  about  20  feet  above  low  water.  The  lower  flat  is  subject 
to  partial  or  complete  overflow  at  the  present  time,  while  the  upper  is  for 
the  most  part,  at  least,  above  high  water. 

“The  composition  of  these  alluvial  deposits  is  commonly  revealed  along 
river  bluffs  and  in  water  wells.  Sandy  clay  predominates,  but  this  gives 
way,  on  the  one  hand,  to  fine  gray  or  blue  clay  or  nearly  normal  loess,  while, 
on  the  other,  to  beds  of  gravel  one  foot  or  more  thick  and  composed  of  flint 
and  sandstone  pebbles  commonly  as  much  as  two  inches  in  diameter.  Vegetal 
remains,  leaves,  and  wood  are  often  interbedded  with  the  silts  while  other 
clays  are  darkly  colored  with  organic  matter. 

“The  thickness  of  the  alluvium  can  be  obtained  only  from  well  borings, 
and  as  these  rarely  penetrate  more  than  a few  feet  to  water,  it  is  not  pos- 
sible to  learn  the  thickness  at  many  places  in  this  area.  At  lower  places  along 
the  Mississippi  it  is  thought  to  be  as  much  as  100  and  200  feet  thick.”1 

i Purdy,  R.  C.,  and  DeWolf,  F.  W.,  Preliminary  Investigations  of  Illinois  Fire  Clay : 
111.  State  Geol.  Survey  Bull.  4,  pp.  145-146,  1907. 


THE  EMBAYMENT  CLAYS 


41 


These  deposits  are  not  utilized  at  the  present  time.  In  the  days  when 
pottery  was  manufactured  at  Metropolis,  slip  clay  was  dug  from  the  Ohio 
River  silt  near  that  place. 

ELEVATION  OF  THE  ILLINOIS  EMBAYMENT  CLAYS 

A study  of  the  relative  elevation  of  the  various  clay  deposits  is  of  inter- 
est as  bearing  on  the  mode  of  origin  and  age  of  the  different  clays.  It  is 
necessary,  however,  to  remember  that  noted  changes  of  elevation  have  taken 
place  in  areas  not  far  distant  from  southern  Illinois  in  recent  times,  as  for 
example  in  the  Reelfoot  Lake  district  of  northwestern  Tennessee,  and  that 
similar  changes  may  have  affected  this  area. 

Approximate  present  elevations  of  clay  beds  above  sea  level 


Clay  “diggins,”  Ramn,  Pope  County 420  to  440 

White  and  lignitic  clays  at  Grand  Chain,  Pulaski  County 425 

Mountain  Glen  clays,  Union  County 400  to  460 

Clay  \l/2  miles  west  of  Alto  Pass,  Union  County 625=*= 

Clay  west  of  Devonian  ridge  at  Kaolin,  Union  County  560 ± 

Clay  east  of  Devonian  ridge  at  Kaolin,  Union  County 560 ± 

Clay  in  southern  Jackson  County 600  to  650 


The  first  three  clays  are  similar  in  many  ways  and  all  are  lignitic  except 
possibly  the  Raum  clay,  in  the  description  of  which  no  mention  was  made 
of  lignite.  The  last  four  clays  are  similar,  in  that  they  are  sandy  and  gen- 
erally have  a greenish  gray  tone. 

Similarity  in  elevation  of  the  first  three  clays  listed  above,  namely,  those 
at  Mountain  Glen,  Grand  Chain,  and  Raum,  suggests  that  they  may  have 
been  of  the  same  age,  though  the  isolation  of  their  positions  makes  accurate 
determination  of  the  age  impossible.  Terrace  clay  100  feet  or  more  above 
the  better  clay  of  the  Union  County  area  points  to  at  least  one  period  of 
clay  formation  subsequent  to  that  of  the  Mountain  Glen  clay. 

The  fact  that  pure,  white,  plastic  clays  of  this  type  are  present  in  small 
isolated  areas  would  seem  to  indicate  that  much  greater  quantities  of  such  fine 
silt  were  washed  into  the  larger  embayment  area  from  the  extensive  Missis- 
sippi limestone  outcrops  and  that  the  present  deposits  are  mere  remnants. 
In  most  cases  sandy  impurities  become  mixed  with  the  silt  in  transportation 
and  the  outer  deposits  are  more  sandy  in  texture.  Such  clays  are  found  in 
the  Wilcox  group  (La  Grange  formation).  “The  clays  * * * vary 

from  pure,  fine-grained,  plastic  material  to  sandy,  silty  clays  that  are  often 
dark  from  organic  matter  or  black  from  lignite.  The  clays  of  the  lower 
part  of  the  formation  are  characteristically  fine-grained,  pure,  plastic,  and 
either  very  light  colored  or  white.”1 

iGlenn,  L.  C.,  Underground  waters  of  Tennessee  and  Kentucky  west  of  Tennessee 
River,  and  in  adjacent  area  in  Illinois : U.  S.  Geol.  Survey  Water  Supply  and  Irrigation 
Paper  164,  p.  34,  1906. 


42 


ILLINOIS  FIRE  CLAYS 


As  mentioned,  clay  dug  near  Hickory,  Kentucky,  and  north  of  Mayfield 
is  identical  in  color,  texture,  and  other  physical  properties  with  that  at 
Mountain  Glen.  That  clay  is  of  Wilcox  age.  All  these  evidences  point  to 
the  Wilcox  age  of  the  Illinois  clays. 

The  higher  sandy  terrace  clays  resemble  the  greenish  gray  clays  at 
Wyckliff,  Kentucky,  and  a later  Wilcox  age  is  suggested  by  their  position. 

The  sandy,  bedded  clays  of  Massac  and  Pulaski  counties  are  in  older 
beds  referred  to  the  Midway  and  McNairy  members. 


Field  and  Laboratory  Notes  on  tiie  Embayment  Clays 

Field  Notes  by  C.  R.  Schroyer 
Tests  by  C.  W.  Parmelee 

UNION  COUNTY,  MOUNTAIN  GLEN  AREA 
PITS  OF  THE  ILLINOIS  KAOLIN  COMPANY 

The  large  pit,  known  as  the  “K”  pit,  of  the  Illinois  Kaolin  Company  is 
located  in  the  SW.  34  sec.  35,  T.  11  S.,  R.  2 W.,  about  a quarter  mile  west 
of  Kaolin  Station  on  the  Mobile  and  Ohio  Railroad.  This  pit  is  approximately 
200  by  300  feet  and  is  about  80  feet  deep  at  the  west  end  where  the  lowest 
working  encountered  a light  to  orange  colored  sand. 

There  is  a variation  in  the  section  from  place  to  place  about  the  walls. 
One  section  measured  at  the  west  end  is  as  follows  i1 


6. 

5. 

4. 

3. 

2. 

1. 


Section  measured  at  the  west  end  of  “K”  pit  of  Illinois 
Kaolin  Company 


Loess  at  top  

Gravel  

Sand,  white,  micaceous ; in  places  stained  pink 
Sand,  pink  to  dark  purplish  red,  micaceous. . . . 

Clay,  pink  to  red,  highly  plastic 

Clay,  bluish  white,  highly  plastic 


Thickness 

Feet 


1 

10 

10 

15 

15 


In  some  places  the  entire  section  is  sand,  gravel,  and  loess,  while  at 
others  clay  extends  from  the  gravel  to  the  bottom  of  the  pit.  A sketch  of 
the  north  wall  made  when  the  pit  was  visited  in  March,  1918,  is  given  in 
Figure  47.  The  sand  rises  as  a huge  dome  and  cuts  out  the  clay  at  its  crest 
over  a 40-foot  width.  Orange  sand  above  is  replaced  by  white  with  occa- 
sional buff  below.  Discoloration  follows  the  line  of  contact  between  the 
sand  and  clay.  White,  purple,  buff,  and  red  are  mottled  in  bands  due  to 
concentration  of  underground  water  circulation  along  channels  of  easiest 
movement.  The  iron  content  of  the  sand  and  the  resultant  firmness  of 
cementation  increase  toward  the  contact  with  the  clay.  Yellow  limonite  is 

1st.  Clair,  Stuart,  Clay  deposits  near  Mountain  Glen,  Union  County,  Illinois : 111. 
State  Geol.  Survey  Bull.  36,  p.  13,  1917. 


UNION  COUNTY 


43 


s 


A °.( 


Loess  and  Gravel  V S { i -/V /Iv  VV  o y A ^ •</•«,> 


Purplish  to  Red  Iron  Oxide : 
: Horizon :v! 


Sand 


40  30  20  10  0 


40 


Scale  In  feet 


N 


:?~~r 


Scale  in  feet 


Fig.  47.  Diagrammatic  sketches  of  the  “K”  pit  of  the  Illinois  Kaolin  Company. 
Above  : North-south  profile  section.  Below  : Sketch  of  the  north  face. 


44 


ILLINOIS  FIRE  CLAYS 


evident,  but  Indian  red  hematite  predominates.  At  each  contact  zone  there 
is  a layer  of  iron  oxides,  generally  impure  from  admixtures  of  sand  and 
clay,  though  several  large  hand  specimens  of  pure  hematite  were  broken  from 
these  seams.  Beyond  the  contact  this  iron  band  grades  from  hematite 
through  limonite  into  red,  purple,  and  mottled  clay.  Concretions  of  iron 
oxide  may  be  found  20  feet  or  more  from  the  contact. 

Along  this  zone  of  iron,  more  commonly  on  the  side  of  the  clay,  are 
numerous  lenses,  pellets,  and  plate-like  stringers  of  clay  with  perfect  slicken- 
sided  surfaces  and  coatings  of  felty  flakes  of  white  mica.  Such  smoothed 
zones  may  be  seen  out  six  feet  or  more  from  the  contact,  separated  not 


Fig.  48.  View  of  the  southwest  wall  of  the  “K”  pit  of  the  Illinois  Kaolin  Company. 

uncommonly  by  thin  sheetings  of  sand.  Lines  of  weakness  extend  far 
beyond  these  smoothed  pellets,  as  shown  in  some  places  by  checks  in  the 
clay,  and  in  others  only  upon  the  weathering  of  the  clay  after  exposure. 
Such  lines  are  roughly  parallel  to  the  line  of  contact  between  the  sand  and 
clay.  A few  larger  spalls  of  clay  are  caught  and  completely  surrounded  by 
the  sand.  Rarely  is  a large  quantity  of  sand  included  within  the  clay,  but 
if  so  included,  it  is  drawn  out  into  a thin  flattened  stringer  bounded  on  each 
side  by  slickensided  clay  pellets. 

These  zones  have  so  conspicuous  a color  when  freshly  exposed  that 
they  stand  out  and  can  be  traced  by  the  eye  from  the  far  side  of  the  pit. 
The  purple  iron  zone  is  reported  to  have  been  lower  in  the  direction  of  the 


UNION  COUNTY 


45 


limestone  wall  at  the  south  and  to  have  everywhere  been  underlain  by  sand. 
This  relation  of  sand  to  clay,  due  to  a doming  of  the  sand  up  into  and 
through  the  clay  may  explain  many  of  the  irregularities  found  in  the  clay 
of  the  district.  Later  drilling  is  reported  to  have  revealed  another  body 
of  clay  with  almost  vertical  walls  northwest  of  the  present  pit,  presumably 
adjoining  the  sand  dome  on  the  northwest. 

Pyrite  occurs  at  certain  levels  near  one  edge  and  a few  thin  lenses  of 
lignite  were  found. 

Details  of  the  working  of  this  pit  and  the  surrounding  property  are 
given  by  St.  Clair  in  State  Geological  Survey  Bulletin  36  and  will  be 
repeated  here  only  briefly.  The  clay  is  dug  by  steam  shovel,  hauled  by  small 
steam  engine  to  a large  shed  east  of  the  mouth  of  the  pit,  cleaned  by  hand, 
graded,  and  stored  or  loaded  directly  onto  the  Mobile  and  Ohio  Railroad 
switch.  Large  quantities  of  clay  have  been  dug  and  one  wall  now  shows  an 
exposure  of  20  feet  of  variegated,  purple  and  white  clay  above  35  feet  of 
white  and  bluish  white,  highly  plastic  clay.  The  greatest  overburden  is  40 
feet  with  an  average  of  15  feet  or  perhaps  more. 

The  southwest  wall  of  the  “K”  pit  is  cliff  of  limestone  (fig.  48),  and 
the  relation  of  the  clay  to  this  wall  suggests  that  it  was  deposited  in  depres- 
sions bordered  at  least  partly  by  the  limestone. 

Two  other  pits  designated  as  the  “G”  and  the  “F,”  are  located  on  this 
same  property,  north  and  west  of  the  present  “K”  pit. 

PITS  OF  THE  FRENCH  CLAY  BLENDING  COMPANY 

The  pit  of  the  French  Clay  Blending  Company  in  the  NW.  sec.  35, 
T.  11  S.,  R.  2 W.,  was  not  in  operation  when  visited.  Judging  from  former 
records  and  from  the  fact  that  clay  outcrops  in  a gully  not  far  from  the 
pits,  the  workings  probably  represent  one  of  the  largest  remaining  clay 
deposits  of  the  area.  One  exposure  of  bed  rock  just  southeast  of  the  former 
pit  is  an  unfossiliferous  limestone  with  chert,  which  dips  14°  NE.  and 
strikes  N.  28°  W. 

This  clay  was  mined  by  shafts  and  connecting  drifts,  and  by  open  pits. 

No  sample  was  obtained. 


GOODMAN  PIT 

Location  and  Method  of  Working 

The  pit  owned  and  operated  by  Dr.  Goodman  of  Cobden  is  located  in 
the  NW.  %.  sec.  2,  T.  12  S.,  R.  2W.  (fig.  49).  The  clay  is  obtained  from 
shafts  14  by  14  feet,  that  are  tightly  cribbed,  sheeted,  and  intercrossed  with 
strong  log  braces  set  in  about  three  feet  from  each  side.  When  one  shaft 
reaches  the  bottom  of  the  clay  it  is  abandoned  and  partly  filled  with  the 
overburden  from  the  next  shaft  which  is  dug  so  that  it  adjoins  the  old  one 


46 


ILLINOIS  FIRE  CLAYS 


by  half  the  length  of  one  of  its  sides.  This  method  recovers  all  the  clay 
with  a minimum  working  of  overburden. 

Stripping  and  digging  from  an  open  pit  would  reduce  the  cost  of  pro- 
duction. Prospecting  by  drill  and  pits  would  outline  the  shape  of  the 
deposit  and  the  quantity  available,  and  thus  indicate  the  development  justified. 

Geology 

The  log  of  the  working  shaft,  which  was  down  about  100  feet  when 
visited  March,  1918,  is  as  follows: 


Fig.  49.  View  of  Dr.  Goodman’s  mine  in  the  NW.  M sec.  2,  T.  12  S.,  R.  2 W. 

Log  of  the  Goodman  shaft  in  the  NW.%  sec.  2,  T.12S.,  R.2W . 

Thickness  Depth 
Feet  Feet 

Description  of  strata 


Loess  10  10 

Gravel  1 11 

Sand  2 13 

Clay 

fPink  clay  (Sample  No.  27) 27  40 

•j  White  and  pink  (Sample  No.  28) 30  70 

(^White  clay  (to  bottom  of  pit)  (Sample  No.  25) 30—}—  100 

Sand,  orange  


UNION  COUNTY 


47 


The  pink  clay  is  reported  to  have  an  approximately  uniform  thickness 
over  the  deposit  so  far  as  worked.  The  white  clay  is  increasing  in  quantity 
and  quality  as  the  pits  are  driven  farther  south  in  the  ridge,  for  accompany- 
ing the  rise  in  the  upper  surface  is  a lowering  of  the  base.  The  results  of 
tests  made  on  samples  No.  27,  No.  28,  and  No.  25  are  given  on  pages  53-56. 

One  small  pocket  of  lignite  has  been  found  in  the  white  clay  and  five  or 
six  perfectly  smoothed  and  polished  pebbles  have  been  taken  from  the  lower 
levels.  The  top  of  the  clay  rises  south  under  the  ridge  and  the  relation  to 


the  sand  at  the  base  suggests  irregularities  similar  to  those  in  the  Illinois 
Kaolin  Company’s  pit.  A sketch  made  at  the  mouth  of  the  shaft  (fig.  50) 
shows  the  relation  of  this  thickening  to  the  overlying  sand  and  gravel.  In 
addition  to  the  samples  noted  above,  a sample  of  the  “Chocolate”  (sample 
No.  30)  clay  which  is  found  associated  with  the  white  clay  was  taken,  and 
the  results  of  tests  made  on  it  are  given  on  pages  56  and  57. 


48 


ILLINOIS  FIRE  CLAYS 


MINES  OF  FREDERICK  E.  BAUSCH 
LOCATION  AND  METHOD  OF  WORKING 

The  present  Bausch  workings  include  three  pits.  No.  1 mine,  located 
near  the  center  of  sec.  35,  T.  11  S.,  R.  2 W.,  is  reported  to  have  reached  a 
depth  of  55  to  60  feet.  Tunnels  driven  from  shafts  at  various  levels  total 
500  feet.  The  overburden  of  ten  feet  has  two  feet  of  gravel  at  the  base. 
The  clay  is  underlain  by  white  sand.  Both  pyrite  and  lignite  are  present 
commonly  occurring  together.  Pink  clay  is  wanting  in  this  deposit. 

At  mine  No.  2 in  the  NE.  cor.  of  SW.  Yl  sec.  35,  T.  11  S.,  R.  2 W., 
the  section  is  given  as  follows : 

Section  measured  at  Bausch  Mine  No.  2 in  sec.  35,  T.  11  S.,  R.  2 W. 

Thickness 

Feet 


3.  Soil  15 

2.  Sand,  reddish,  coarse,  gravelly  (vertical  seam) 40 

1.  Clay,  one  side  of  shaft  pink,  other  side,  white 25 


Mine  No.  3 is  located  in  the  SE.  )4  sec.  27,  T.  11  S.,  R.  2 W.,  near 
the  center  of  the  east  line  of  the  section,  about  one  mile  from  the  loading 
stage  at  Kaolin.  The  mining  is  by  shaft  and  tunnels,  and  the  clay  is  said  to 
be  drifting  down  following  the  quicksand  below.  At  the  present  working 
it  is  30  feet  thick,  with  an  overburden  of  about  18Y  feet.  The  clay  is 
assorted  and  trimmed  by  hand. 

Three  grades  of  clay  are  made:  namely,  A1  or  No.  3 (sample  No.  121), 
Blue  No.  2 (sample  No.  122),  and  No.  1 (sample  No.  9)  ; tests  were  made 
on  these  samples  with  the  results  given  on  pages  57  to  59. 

Geology 

This  pit  is  located  between  upthrown  Mississippian  limestone  at  the 
east  and  the  Devonian  highlands  at  the  west.  The  limestone  outcrops  in  a 
scarp  less  than  200  yards  east  of  the  pit,  dips  20°  E.,  and  strikes  N.  15°  W. 
Drillings  by  the  Illinois  Kaolin  Company  south  of  this  pit  near  the  NE. 
cor.  sec.  34  show  only  black  pyritic  Devonian  shale.  The  clay  is  evidently 
in  an  isolated  depression. 


ELMER  GANT  MINE 

The  Gant  clay  mine  is  located  in  the  SE.  % SE.  % sec.  2,  T.  12  S., 
R.  2 W.,  about  \y2  miles  by  wagon  road  from  the  Mobile  and  Ohio  Railroad 
switch  at  Kaolin.  The  clay  is  mined  from  a shaft  14  by  14  feet  with  “lead 
tunnels.”  It  is  drawn  out  by  horse  and  bucket  and  the  better  grades  are 
assorted  and  trimmed  by  hand.  Three  grades  are  made,  pink  and  white 
mottled,  No.  3 (sample  No.  29)  ; white,  No.  2 (sample  No.  23)  ; and  the 
bluish  white,  No.  1 (sample  No.  26)  ; tests  of  these  samples  are  reported  on 
pages  59  to  61. 


UNION  COUNTY 


49 


The  overburden  of  loess  and  gravel  is  from  6 to  12  feet  thick.  Several 
test  pits  have  been  dug  and  borings  have  been  made ; one  is  reported  to  have 
gone  73  feet  in  clay.  The  present  workings  are  35  feet  deep. 

But  very  small  amounts  of  lignite  have  been  found  associated  with  the 
clay  and  no  pyrite  is  reported. 

This  clay  is  obtained  from  a hollow  on  the  west  side  of  a loess-covered 
ridge.  On  the  opposite  side,  beds  of  crystalline  Mississippian  limestone  are 
found  in  place  and  loose  slabs  extend  up  to  a level  which  is  not  far  below 
the  top  of  the  clay. 

T.  P.  SIFFORD  PIT 

A pit  opened  by  T.  P.  Sifford  is  located  on  the  Mary  A.  Walker  farm 
in  the  SW.  Y\  sec.  1,  T.  12  S.,  R.  2W.  The  overburden  does  not  exceed 
15  feet.  The  present  shaft,  a double  hoist,  15  by  10  feet,  has  been  dug  62 
feet  deep  into  50  feet  of  clay.  A boring,  it  is  said,  penetrated  72  feet  of  clay. 
White  clay  is  reported  to  be  above  and  pink  below.  In  one  side  of  the  pit 
a streak  of  lignite  was  associated  with  concretions  of  pyrite  and  marcasite. 

This  pit  is  little  more  than  a quarter  of  a mile  east  of  the  Gant  pit  and 
is  separated  from  it  by  a high  loess-covered  ridge  and  the  crystalline  limestone 
mentioned  above.  A pit  35  feet  deep,  dug  100  feet  south  of  the  shaft, 
penetrated  nothing  but  orange  sand,  below  the  gravel,  indicating  a condition 
similar  to  that  found  in  the  Illinois  Kaolin  Company’s  pit. 

No  clay  has  been  shipped  from  this  pit. 

MADDOX  AND  NIXON  PIT 

The  Maddox  and  Nixon  clay  mine  is  located  in  the  NE.  J4  sec.  10, 
T.  12  S.,  R 2 W.,  less  than  half  a mile  west  of  the  loading  switch  on  the 
Mobile  and  Ohio  Railroad.  Six  14-  by  14-foot  cribs  have  been  mined  from 
clay  reported  to  be  from  12  to  35  feet  thick.  The  top  of  the  clay  rises  and 
the  base  lowers  as  the  pits  are  driven  farther  back  into  the  ridge.  Three 
grades  of  clay  have  been  obtained:  No.  1,  blue  clay  (sample  No.  11); 
No.  2,  white  clay  (sample  No.  16)  ; and  No.  3,  pink  and  white  mottled  clay. 
The  best  grade  comes  from  the  lower  parts  of  the  pits.  Results  of  tests 
made  on  samples  No.  11  and  No.  16  are  given  on  pages  61  and  62. 

The  overburden  is  about  12  feet  thick.  White  sand  underlies  the  clay. 

SMALLER  PITS 

Much  prospecting  done  outside  of  the  main  clay  area,  has  discovered  a 
few  small  lenses  of  clay. 

Wm.  Ferril  dug  a small  amount  of  sandy  clay  from  pits  in  the  NE.  ^4 
sec.  3,  T.  12  S.,  R.  2 W.  Much  sand  and  gravel  accompanies  this  clay  and 
the  quantity  is  probably  small. 

Samples  No.  18  and  No.  22  were  taken  from  this  property,  and  reports 
on  their  testing  are  given  on  pages  62  and  63.  The  latter  is  Ferrill’s  best  or 
“Blue”  clay. 


50 


ILLINOIS  FIRE  CLAYS 


Fig.  51. 


Map  of  the  Mountain  Glen  area.  The  lands  known  to  include  deposits  of 
having  proven  or  probable  commercial  value  are  indicated  by  shading 


The  following  list  contains  the  names  of  the  owners  of  the  several  pits  or 
mines  shown  on  the  above  map  : 

1.  Frederick  E.  Bausch  (Mine  No.  3.) 

2.  French  Clay  Blending  Company 

3.  Frederick  E.  Bausch  (Mine  No.  2) 

4.  Illinois  Kaolin  Company  (3  pits) 

5.  Frederick  E.  Bausch  (Mine  No.  1) 

6.  Dr.  Goodman 

7.  Elmer  Gant 

8.  Maddox  and  Nixon 


UNION  COUNTY 


51 


Another  pit  has  been  opened  in  the  NE.  sec.  17.  T.  11  S.,  R.  2 W., 
where  the  clay  is  sandy  and  mixed  with  red  surface  clay  at  the  top.  No 
clay  has  been  shipped.  This  is  at  an  elevation  of  about  625  feet  above  sea 
level. 

Much  other  prospecting  has  been  done,  and  it  is  hardly  likely  that  there 
are  many  deposits  of  the  high  grade  clay  that  are  not  now  known.  Figure  51 
is  a map  of  the  Mountain  Glen  area  on  which  the  lands  known  to  include 

deposits  of  clay  having  proven  or  probable  commercial  value,  are  indicated 
by  shading. 


COMPARISON  WITH  THE  CLAYS  NEAR  MAYFIELD,  KENTUCKY 

Pink  and  white  clay  reported  to  be  30  feet  thick  is  dug  on  the  D.  M. 
Chapman  farm  2^2  miles  west  of  Hickory,  Kentucky.  The  pink  clay  is 
mostly  at  the  top  and  there  is  some  coloring  from  lignite.  Similar  clay  is  also 
dug  3 miles  west  of  Hickory,  where  the  average  thickness  is  about  16  feet. 
These  clays  are  in  the  lower  part  of  the  Wilcox  group. 

In  color,  texture,  and  physical  properties  these  clays  resemble  the  Union 
County  clays  of  Illinois.  The  presence  of  lignite  and  the  lack  of  stratification 
is  common  to  both. 

COMPARISON  WITH  THE  CLAYS  OF  LUTESVILLE,  MISSOURI 

In  texture  and  color  the  clays  of  Union  County,  Illinois,  are  similar  to 
the  kaolin  of  the  Lutesville  district,  Missouri.  Those  clays,  however,  are 
thought  to  occupy  the  same  position  as  the  bed  rock  from  which  they  were 
derived  and  are  a residual  product  from  the  decay  of  a sedimentary  rock, 
presumably  a cherty  limestone  interbedded  with  thinner  beds  of  siliceous 
strata.  This  decay  seems  to  have  been  localized  along  fault  planes.  In  the 
Bausch  mine,  two  miles  west  of  Glen  Allen,  a sandstone  bed  is  now  repre- 
sented by  three  feet  of  quartzite  30  feet  below  the  top  of  the  shaft.  This  is 
interbedded  with  white  kaolin  above  and  below.  Traces  of  former  bedding 
planes  are  evident  in  the  walls  of  the  mine  and  irregular  seams  of  chert 
parallel  the  bedding  and  sets  of  fracture  lines.  Large  numbers  of  chal- 
cedonic  nodules  suggest  considerable  solution,  concentration,  and  redeposition 
of  silica,  though  part  of  the  siliceous  material  is  still  distributed  as  stringers 
and  beds  of  granular  white  “tripoli.”  In  some  of  the  concretionary  masses 
such  silica  has  served  as  the  nucleus  of  deposition  and  is  now  enclosed  in  a 
coating  of  hard,  banded  chalcedony. 

The  clay  varies  from  white  through  grayish- white  to  reddish  pink. 

The  presence  of  lignite  and  an  occasional  pebble  in  the  Illinois  clays  is 
proof  of  reworking,  transportation,  and  redeposition,  or,  in  other  words,  of 
a sedimentary  clay  in  contrast  to  the  similar  clay  in  Missouri  which  is  still 
residual. 


52 


ILLINOIS  FIRE  CLAYS 


RESULTS  OF  TESTS 

UNION  COUNTY,  MOUNTAIN  GLEN  AREA 

Samples  F,  G,  and  K3 

(Illinois  Kaolin  Company;  SW.  J/4  sec.  35,  T.  11  S.,  R.  2 W.) 

Three  samples  of  clays  received  from  the  Illinois  Kaolin  Company  prior  to  the 
visit  of  members  of  the  Survey  were  tested  with  the  results  as  shown  under  the 
headings  F,  G,  and  K3. 


(F) 

(G) 

(K3) 

Water  of  plasticity 

37.4 

41.4 

Shrinkage  water  

18.9 

24.0 

Pore  water  

18.5 

17.4 

Modulus  of  rupture  

. .Ibs.  per  sq.  in. 

142.5 

145 

195.6 

With  50%  standard  sand — Modulus  of  rupture.. 

. .lbs.  per  sq.  in. 

259.5 

163.7 

202.8 

Slaking  test  

21 

21^2 

Screen  test : — 


(Sample  F) 


Mesh  Residue  Character  of  residue 

Per  cent 

20 13  Silica  and  particles  of 

coal 

40 10  Quartz  particles,  some 

colored  with  iron 

60 47  Quartz  particles,  round- 

ed, colored  with  iron 

80 13  Clear  quartz  particles 

120 3.14  White  and  brown 

quartz  particles 

200 1.4  White  quartz  particles 


(Sample  G) 

120 37 

200 22 

Drying  shrinkage : — 


Linear ; wet  length  

Linear ; dry  length  

Volume  

Burning  test : — 

(Sample  F) 


Burning 

Cone  Porosity  Color  shrinkage 

Percent  Percent 

2 19.9  9.2 

5 6.6  Cream  11.0 

9 3.2  Gray  exterior ; bluestoned 11.5 

12  3.96  Tan  exterior;  bluestoned 10.8- 

13j/2  3.68  10.6 

15  4.2  Tan  exterior;  bluestoned 11.0 


White  quartz  particles 
Quartz  sand 


-Per  cent- 


(F) 

(G) 

(K3) 

5.26 

5.27 

10.0 

5.68 

5.68 

11 

28 

29 

40.2 

Remarks 


Hackly  fracture 


UNION  COUNTY 


53 


(Sample  G) 


2 

25.1 

White  

...  5.9 

5 

18 

Cream  white 

...  8.4] 

9 

7.55 

Cream  

...  9.2 1 

12 

2.81 

9 4 ( 

13 

2.57 

...  11.41 

15 

3.26 

Tan  exterior  ; bluestoned. . . . 

...  11.1 

Hackly  fracture 


Hackly  fracture ; vein- 
ing  of  fine  cracks  in 
the  surface 


(Sample  K3) 


04 

34 

Cream  white  

...  4.3" 

I 

02 

33 

Cream  white 

...  4.8 

! 

2 

20 

Cream  white  

i 

>-  Hackly  fracture 

5 

21 

Cream  white  

...  9.0 

9 

7 

Cream  white  

...  12.0J 

13 

3 

Gray  white  ; bluestoned 

Fine-meshed  surface 
cracks 

14 

3 

Tan  exterior  ; bluestoned. . . . 

...  13.0 
(F) 

(G)  (K3) 

Fusion 

test  

Cone  29/30  Cone  32 

Summary 

Samples  F,  G,  and  K3  are  all  similar  in  appearance,  excepting  for  the  slight 
differences  in  color.  In  plasticity  and  working  properties  there  is  little  difference. 
They  are  all  similar  in  having  a higher  strength  when  mixed  with  standard  sand 
than  when  tested  as  pure  clay.  The  bonding  strengths  of  K3  and  F are  medium.  G is 
low.  The  amount  of  residue  left  on  the  various  sizes  of  screen  mesh  is  exceedingly 
small.  The  drying  shrinkage  of  K3  is  medium  high  while  that  of  F and  G is  medium 
low.  The  burning  shrinkages  at  cone  9 are  high  for  all  three  samples.  The  sample 
F is  well  vitrified  at  cone  9,  while  the  other  samples  are  slightly  less  so  at  the  same 
temperature.  These  are  refractory  clays,  which  do  not  overburn  at  cone  15. 

These  clays  belong  to  a class  which  has  been  found  very  useful  for  admixture 
with  others  in  the  production  of  close  burning  refractory  bodies ; also  of  bodies 
not  of  refractory  nature  but  of  close  texture  or  having  a high  content  of  non-plastic 
material  which  must  be  well  bonded  together. 

Sample  No.  27 

(Goodman  pit ; NW.  *4  sec.  2,  T.  12  S.,  R.  2 W.) 

This  is  a soft  pinkish-colored  clay,  varying  somewhat  in  shade  and  showing  an 
occasional  yellowish  streak.  The  working  properties  of  the  plastic  mass  are  good. 
It  flows  through  a die  satisfactorily  when  in  a stiff  condition. 


Water  of  plasticity  per  cent  36.4 

Shrinkage  water  per  cent  8.2 

Pore  water  per  cent  28.2 

Modulus  of  rupture lbs.  per  sq.  in.  265 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  120.9 

Slaking  test,  average  min.  20 


54 


ILLINOIS  FIRE  CLAYS 


Screen  test : — 


Mesh  Residue  Character  of 

Per  cent  residue 

120 015  Fine  sand 

150 57  Sand 

200 63  Sand 


Drying  shrinkage : — 


Linear;  wet  length  

Linear;  dry  length  

Volume  

Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

2 23  Pink 9.57 

5 14  Pink 10.85 

9 2.6  Light  tan ; bluestoned 12.0 

12  1.6  Light  tan  exterior;  heavily  blue- 

stoned  

13  7 Light  tan  exterior ; heavily  blue- 

stoned  9.27 

15  6.24  Dark  buff ; bluestoned 10.4 

Fusion  test: — It  deforms  at  29/30  cone. 


Per  cent 
..  6.7 
. . 7.38 

..  29.4 


Remarks 


Hackly  fracture 
Hackly  fracture 


Fine  mesh  of  cracks 


Summary 

The  strength  of  the  unburned  clay  is  medium.  The  bonding  strength  is  medium 
low.  The  percentage  of  residues  left  on  the  screens  is  slight.  The  drying  shrinkage 
is  medium.  The  total  shrinkage  at  cone  9 is  medium  high.  Vitrification  is  complete 
at  cone  12.  The  apparent  overburning  at  cone  13^4  may  be  due  to  the  development 
of  small  cracks  in  the  test  piece  during  the  firing  since  there  is  no  further  increase  in 
the  porosity  at  cone  15.  It  is  a refractory  clay.  This  clay  is  adapted  for  use  in  the 
manufacture  of  refractories,  especially  those  which  burn  densely.  This  clay  burns  to 
a very  dark  color  for  a fire  clay. 


Sample  No.  28 

(Goodman  pit;  NW.  % sec.  2,  T.  12  S.,  R.  2 W.) 

This  is  a soft  clay  varying  in  color  from  cream  to  red.  The  plastic  mass  is  readily 


molded.  It  flows  poorly  through  the  die. 

Water  of  plasticity per  cent  38.3 

Shrinkage  water per  cent  18.7 

Pore  water per  cent  19.5 

Modulus  of  rupture lbs.  per  sq.  in.  192.7 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  151.8 

Slaking  test,  average min.  10.5 

Drying  shrinkage : — 

Per  cent 

Linear ; wet  length  7.45 

Linear;  dry  length  8 

Volume  30.9 


UNION  COUNTY 


55 


Burning  test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

01 

30 

Pinkish  white  

7.42 

3 

16 

Light  cream 

11.1 

4 

10.1 

Light  cream 

11.7 

6 

7 

Cream 

12.0 

Hackly  fracture 

9 

3.0 

Cream ; bluestoned  

12.9] 

12 

2.5 

Gray;  bluestoned  

13.5} 

Vitreous ; hackly 

13 

3.4 

Cream ; bluestoned  

13.6) 

fracture 

15 

4.7 

Tan  exterior  ; bluestoned. . 

13.4 

Hackly  fracture.  Fine 

veining  of  cracks 
throughout  test  piece 

Soluble  salts : — Pieces  burned  at  the  low  cones  show  strongly  characteristic  yellowish 
surface  coating  after  soaking  in  water. 

Fusion  test : — It  deforms  at  cones  32/33. 


Summary 

This  clay  has  a medium  low  strength  in  the  unburned  condition.  Its  bonding 
strength  is  low.  The  absence  of  residues  on  the  screens  indicates  a very  fine-grained 
material.  The  drying  shrinkage  is  medium.  The  total  shrinkage  at  cone  9 is  high. 
Vitrification  is  nearly  complete  at  cone  12.  The  clay  is  highly  refractory  and  is  espe- 
cially adapted  to  the  manufacture  of  such  wares,  especially  those  which  should  burn 
dense  at  a low  temperature. 


Sample  No.  25 


(Goodman  pit;  NW.  % sec.  2,  T.  12  S.,  R.  2 W.) 

This  is  a white  clay  which  shows  a few  reddish  stains  on  the  faces  of  fractures. 
Its  working  properties  in  the  plastic  condition  are  good.  When  the  clay  is  in  a stiff  con- 


sistency it  flows  satisfactorily  through  a die. 

Water  of  plasticity  per  cent  39.5 

Shrinkage  water  per  cent  19.4 

Pore  water  per  cent  20 

Modulus  of  rupture lbs.  per  sq.  in.  131.2 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  141.4 

Slaking  test,  average  min.  12 

Drying  shrinkage : — 


Per  cent 

Linear ; wet  length  8.3 

Linear;  dry  length  9.1 

Volume  32 

Burning  test : — 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

23.7 

Cream 

....  8.45 

5 

20 

Cream  

. . . . 9.15] 

9 

3.6 

Gray ; bluestoned  

....  10.9 

12 

0.7 

Gray ; bluestoned  

....  11.9 

Hackly  fracture 

1314 

0.9 

....  12.5 

15 

3.0 

Gray  exterior ; bluestoned.. 

....  11.8 

Fusion  test: — It  deforms  at  cone  32. 


56 


ILLINOIS  FIRE  CLAYS 


Summary 

The  strength  of  the  unburned  clay  is  medium  low.  Its  bonding  strength  is 
medium  low.  Practically  no  residues  are  retained  on  the  screens.  The  drying  shrink- 
age is  medium.  The  total  burning  shrinkage  at  cone  9 is  high.  Vitrification  is  com- 
plete at  cone  12.  Overburning  seems  to  be  indicated  at  cone  15.  It  is  quite  possible 
that  this  appearance  is  due  to  the  peculiar  cracking  of  the  piece  rather  than  a real 
vesicular  structure.  It  is  a refractory  clay.  It  is  suggested  that  it  will  find  important 
uses  in  the  manufacture  of  refractories,  especially  those  requiring  a dense  structure. 


Sample  No.  30 

(Goodman  pit;  NW.  ^ sec.  2,  T.  12  S.,  R.  2 W.) 

This  is  a soft  clay  of  a cream  color,  shading  into  reddish.  Its  working  prop- 
erties in  the  plastic  condition  are  good.  It  flows  satisfactorily  through  a die  when 
it  has  a stiff  consistency. 

Water  of  plasticity per  cent  44.2 

Shrinkage  water  per  cent  21.4 

Pore  water per  cent  22.8 

Modulus  of  rupture lbs.  per  sq.  in.  345 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  229.4 


Slaking  test  . . 
Screen  test : — 
Mesh 


13 


Residue 
Per  cent 
. 1.46 

. 0.39 

. 0.24 


Character  of 
residue 

Cream-colored  sand 
Cream-colored  sand 
Very  fine  sand 


120 

150 

200 

Drying  shrinkage : — 

Per  cent 

Linear ; wet  length  7.5 

Linear ; dry  length  8.25 

Volume 34.6 

Burning  test 


Cone 

2 

Porosity  Color 

Per  cent 

9%  7 C rpam  

Burning 
shrinkage 
Per  cent 

12.3 

Remarks 

5 

1.3 

Gray  

13.7'| 

9 

3.7 

13.01 

Hackly  vitreous  frac- 

12 

3.2 

Tan  exterior ; bluestoned  interior  13.2  f 

ture 

13 

0.1 

12.4 1 

15 

53 

Buff ; bluestoned  . 

11.4 

Hackly  vitreous  frac- 

ture.  Surface  cov- 
ered with  mesh  due 
to  cracks 

Soluble  salts: — Piece  burned  at  cone  2 after  soaking  in  water  shows  greenish-yellow 
surface  coating.  Possibly  vanadium  salts. 

Fusion  test : — It  fused  at  cone  32. 


Summary 

The  strength  of  the  unburned  clay  is  medium.  Its  bonding  strength  is  medium. 
The  percentage  of  residues  is  slight.  The  drying  shrinkage  is  medium.  The  total 


UNION  COUNTY 


57 


shrinkage  at  cone  9 is  high.  Practically  complete  vitrification  is  reached  at  cone  5 
and  overburning  is  slight  if  any  at  cone  15. 

Suggested  uses : Refractories,  particularly  crucibles  and  glass  pots,  etc. ; archi- 
tectural terra  cotta,  sanitary  ware,  stoneware. 

Sample  No.  121 

(Frederick  E.  Bausch  mines;  near  Mountain  Glen) 

This  is  a soft  white  clay.  When  tempered  with  water,  it  becomes  very  plastic 
and  inclined  to  be  sticky.  It  flows  very  poorly  through  the  die. 

Water  of  plasticity per  cent  37.1 

Shrinkage  water per  cent  20.9 

Pore  water per  cent  16.2 

Modulus  of  rupture lbs.  per  sq.  in.  191 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  123.3 


Slaking  test,  average 
Screen  test : — 

Mesh 


, min.  22-}- 


60 

80 

120 

200 

Drying  shrinkage : — 

Per  cent 

Linear ; wet  length  7.4 


Residue 
Per  cent 
. Trace 
. Trace 
. .09 

. .24 


Character  of 
residue 


Sand 


Fine  white  sand 
White  sand  and  mica 


Linear ; dry  length 

Volume  

Burning  test: — 


8.2 

33.5 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

18.3 

Cream  white  

....  8.3 

Hackly  fracture 

5H 

13.0 

Cream  white 

....  8.8^ 

9 

1.68 

Gray ; bluestoned  

....  9.6 

12 

1.40 

Gray;  bluestoned  

....  10.3 

Hackly  vitreous  frac- 

13X 

2.0 

Gray ; bluestoned  

....  9.8 

ture 

15 

2.5 

Gray  exterior;  bluestoned.. 

....  9.3  J 

Fusion  test: — It  deforms  at  cone  30. 


Summary 

The  clay  has  a medium  low  strength  and  medium  low  bonding  strength.  The 
amount  of  screen  residues  is  negligible.  The  drying  shrinkage  is  medium.  The  total 
shrinkage  at  cone  9 is  high.  Vitrification  is  practically  complete  at  cone  9 and  the 
clay  is  not  overburned  at  cone  15.  The  clay  is  refractory. 

This  is  the  type  of  clay  which  is  useful  in  the  manufacture  of  dense  burning 
refractories. 


Sample  No.  122 

(Frederick  E.  Bausch  mines ; near  Mountain  Glen) 

This  is  a soft  white  clay  which  becomes  very  plastic  when  tempered  with  water. 
It  is  also  somewhat  sticky.  It  flows  badly  when  forced  ..through  a die. 


58 


ILLINOIS  FIRE  CLAYS 


Water  of  plasticity  

Shrinkage  water  

Pore  water  

Modulus  of  rupture 

With  50%  standard  sand — Modulus  of  rupture 

Slaking  test,  average  

Screen  test : — 

Mesh 

120 

200 


per  cent  37.9 

per  cent  20.6 

per  cent  17.3 

lbs.  per  sq.  in.  177.0 
lbs.  per  sq.  in.  136.5 
min.  29-f- 


Residue  Character  of 

Per  cent  residue 

.25  White  sand 

.10  White  sand 


Drying  shrinkage : — 

Per  cent 


Linear ; wet  length  7.4 

Linear ; dry  length 7.8 

Volume  35 


Burning 

Cone 

test : — 

Porosity 

Color 

Burning 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

20.0 

Cream  white 

8.0 

3 

13.3 

Cream  white 

Cracked  along  lines  of 

differential  flow 

6 

10.0 

Darker  cream  white. . 

'i 

9 

1.3 

Gray ; bluestoned  . . , 

12 

2.8 

Gray  , 

9.7 

► 

Hackly  fracture 

m 

2.4 

Gray  

10.4 

15 

3.3 

Gray  to  tan  exterior ; 

bluestoned  10.2 

Fusion  test: — Down  at  cone  32.  Not  vesicular. 


Summary 

The  strength  of  this  clay  with  and  without  the  addition  of  standard  sand  is 
medium  low.  It  has  a very  fine  texture,  leaving  hardly  more  than  a trace  of  residue 
upon  the  screens.  The  drying  shrinkage  is  medium  and  the  total  shrinkage  at  cone  9 
is  high.  Vitrification  is  practically  complete  at  cone  9 and  the  slight  increases  in 
porosity  at  the  higher  cones  is  apparently  due  to  the  formation  of  fine  cracks  which 
permeate  the  mass,  rather  than  due  to  overburning.  It  is  a refractory  clay. 

Suggested  Uses : This  clay  belongs  to  the  type  of  refractory  clays  which  is  of 
importance  in  the  preparation  of  refractory  wares  having  a dense  structure.  It  is  also 
similar  to  the  architectural  terra  cotta  and  stoneware  clays,  although  it  is  doubtful 
that  it  could  be  used  alone  to  advantage  for  the  latter  purpose. 


Sample  No.  9 

(Frederick  E.  Bausch  mines;  near  Mountain  Glen) 

This  is  a soft  clay  of  a pink  color  with  streaks  of  brownish  yellow  and  red. 
Its  working  property  is  fair,  and  it  is  rather  sticky.  Its  conduct  when  flowing  through 


a die  is  fair. 

Water  of  plasticity  per  cent  32.7 

Shrinkage  water per  cent  23.5 

Pore  water per  cent  9.2 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  104.4 

Slaking  test,  average min.  19 

Fusion  test: — It  deforms  at  cone  31. 


UNION  COUNTY 


59 


Summary 

This  clay  is  slightly  more  refractory  than  Nos.  121  and  122  but  similar  to  them  in 
its  properties  in  both  the  unburned  and  the  burned  condition. 


Sample  No.  29 

(Elmer  Gant  mine;  SE.  *4  SE  *4  sec.  2,  T.  12  S.,  R.  2 W.) 

This  is  a soft  white  clay,  marked  by  a few  yellow  and  a few  black  veins.  Some 
of  the  pieces  are  of  a pronounced  yellowish  color.  Its  working  properties  in  the 
plastic  condition  are  good  except  that  it  is  somewhat  sticky.  Its  conduct  when  flow- 
ing through  a die  is  fair. 

Water  of  plasticity per  cent  35.8 

Shrinkage  water  per  cent  18.7 

Pore  water  per  cent  17.1 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  286.12 

Slaking  test,  average  min.  16 

Screen  test: — 

Mesh  Residue  Character  of 

Per  cent  residue 

120 0.45  White  sand 

200 0.23  White  sand 


Drying  shrinkage : — 


Linear ; dry  length 
Linear ; wet  length 
Volume  


Burning 

Cone 

test : — 

Porosity 

Color 

Burning 

shrinkage 

j 

Per  cent 
20.4 

Light  cream  

Per  cei 
....  7.4] 

it 

2^ 

11.3 

Light  cream  

...  9.6 

3 

10.6 

Light  cream  

. . . . 9.6 

6 

2.3 

Cream 

. ...  10.0 

8H 

2.0 

Cream;  slightly  bluestoned. 

1 

1 

1 

r 

9 

2.1 

Cream;  slightly  bluestoned. . 

12 

1.9 

Cream ; bluestoned 

. ...  11.0 

13 

2.2 

Cream ; bluestoned 

....  11.0 

15 

3.0 

Tan  exterior ; bluestoned . . 

. . . . 9.6 

Fusion  test : — It  deforms  between  cones  32  and  33. 


Per  cent 
..  6.2 
. . 5.75 

..  30.4 


Remarks 


Hackly  fracture 


Summary 

This  clay  has  medium  strength.  The  percentage  of  residue  is  slight.  The  dry- 
ing shrinkage  is  medium.  The  total  shrinkage  at  cone  12  is  medium  high.  Vitrifica- 
tion is  nearly  complete  at  cone  6.  Suggested  uses  are  refractories,  especially  for 
crucibles  and  other  dense  wares,  architectural  terra  cotta,  stoneware,  sanitary  ware. 


Sample  No.  23 

(Elmer  Gant  mine;  SE.  % SE.  *4  sec.  2,  T.  12  S.,  R.2W.) 

This  is  a white  soft  clay  which  has  some  veins  of  red  through  it.  Its  working 
properties  in  the  plastic  condition  are  good.  It  flows  fairly  well  through  a die. 

Water  of  plasticity per  cent  35.8 

Shrinkage  water  per  cent  19.2 

Pore  water  . . . . per  cent  16  6 


60 


ILLINOIS  FIRE  CLAYS 


Modulus  of  rupture 

With  50%  standard  sand — Modulus  of  rupture 

Slaking  test,  average 

Screen  test : — 

Mesh 

20 

40 

60 

120 

200 

Drying  shrinkage : — 


Residue 
Per  cent 
. Trace 
. Trace 
. Trace 
. 0.2 
. 0.43 


.lbs.  per  sq.  in.  311.2 
lbs.  per  sq.  in.  302.3 
min.  23 

Character  of 
residue 


White  sand 
White  sand 


Per  cent 

Linear ; dry  length  7.7 

Linear;  wet  length  7.1 

Volume  32.5 


Burning  test: — 


Burning 

Cone 

Porosity 
Per  cent 

Color 

shrinkage 
Per  cent 

Remarks 

2 

12.1 

Cream  white  

..  10.0 

3 

4.8 

Cream  white  

. . 9.0 

6 

2.6 

Cream ; bluestoned 

..  9.5 

Hackly  vitreous  frac- 
ture 

9 

2.4 

Cream ; bluestoned 

..  10.0 

Vitreous  fracture 

12 

2.9 

Bluestoned  

..  10.0 

Vitreous  fracture 

13 

1.1 

Light  tan  exterior  ; bluestoned 

Vitreous  fracture 

15 

2.0 

Tan  exterior;  bluestoned 

..  10.0 

Fine  closed  cracks  on 
the  surface 

Fusion  test: — It  deformed  at  cone  32. 

Summary 

The  strength  of  the  unburned  clay  is  medium.  Its  bonding  strength  is  medium. 
The  percentage  of  screen  residues  is  slight.  The  drying  shrinkage  is  medium.  The 
total  shrinkage  at  cone  9 is  high.  Vitrification  is  complete  at  cone  13.  It  is  a re- 
fractory clay.  It  is  suggested  that  it  will  be  found  of  use  in  the  manufacture  of  re- 
fractories requiring  a densely  burned  body  at  a low  temperature,  such  as  crucibles. 


Sample  No.  26 

(Elmer  Gant  mine;  SE.  ^ SE.  % sec.  2,  T.  12  S.,  R.  2 W.) 

This  is  a soft  white  clay  which  may  be  brought  to  a good  plastic  condition  with 
the  development  of  some  stickiness.  It  flows  through  a die  satisfactorily  when  it  is 


in  a stiff  condition. 

Water  of  plasticity per  cent  41.5 

Shrinkage  water  per  cent  25 

Pore  water  per  cent  16.5 

Modulus  of  rupture lbs.  per  sq.  in.  259.0 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  137.5 

Slaking  test,  average min.  34 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  8.4 

Linear ; wet  length  7.64 


UNION  COUNTY 


61 


Burning  test : — 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

16 

10.2 

5 

1.4 

Gray  white  

10.7] 

| 

9 

1.8 

Stoneware  gray  . . 

11.3  | 

12 

2.8 

Light  tan  exterior ; 

heavily  blue- 

K 

Hackly,  vitreous  frac- 

stoned   

11.0 

ture 

13 

3.27 

10.0 

15 

3.0 

Gray  exterior  ; bluestoned 9.1 

Hackly  fracture 

Fusion  test : — It  deformed  at  cone  33. 

Summary 

The  strength  of  the  unburned  clay  in  the  dry  condition  is  medium.  The  bonding 
strength  is  medium  low.  It  leaves  no  residues  on  the  screens.  The  drying  shrinkage 
is  medium.  The  total  shrinkage  at  cone  9 is  high.  Vitrification  is  practically  com- 
plete at  cone  5.  It  is  highly  refractory  clay.  It  is  suggested  that  it  will  find  use  in 
the  manufacture  of  refractories,  especially  those  having  a dense  body. 


Sample  No.  11 


(Aladdox  and  Nixon  mine  ; NE.  14  sec.  10,  T.  12  S.,  R.  2 W.) 


This  is  a plastic  clay  of  a white  color, 
through  a die  quite  satisfactorily. 

Water  of  plasticity 

Shrinkage  water  

Pore  water  

Modulus  of  rupture 

Slaking  test,  average 

Screen  test : — 

Mesh 

40 

60 

80 

120 

200 

Drying  shrinkage,  linear;  dry  length 

Burning  test : — 


It  has  good  working  properties  and  flows 

per  cent  32.9 

per  cent  23.5 

per  cent  9.3 

lbs.  per  sq.  in.  43.4  (?) 

min.  6 


Residue 

Character  of 

Per  cent 

residue 

None 

. 0.03 

White  sand 

. 0.03 

White  sand 

. 0.8 

White  sand,  some  mica 

. 2.1 

White  sand,  some  mica 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Total  shrinkage 

Per  cent 

Per  cent 

Per  cent 

02 

39.6 

Light  cream  

3.8 

8.3 

1 

38.4 

Light  cream  

4.5 

9.0 

3 

31.1 

Light  cream  

7.4 

11.9 

5 

28.8 

Dark  cream  

9.0 

13.5 

7 

15.6 

Dark  cream  

9.9 

14.4 

9 

12.9 

Light  brown  

11.2 

15.7 

13 

6.9 

Light  brown  

. ... 

Fusion  test: — It  deforms  at  cone  33. 


62 


ILLINOIS  FIKE  CLAYS 


Summary 

The  percentage  of  screen  residues  is  slight.  The  drying  shrinkage  is  medium 
low.  The  total  shrinkage  at  cone  9 is  high.  Vitrification  is  incomplete  even  at  cone 
13.  It  is  a highly  refractory  clay.  It  is  suggested  that  it  will  find  use  in  the  manu- 
facture of  refractories  of  a high  grade. 

Sample  No.  16 

(Maddox  and  Nixon  mine;  NE.  % sec.  10,  T.  12  S.,  R.  2 W.) 

This  is  a soft  clay  of  nearly  white  color.  Its  working  property  is  good.  Its  con- 
duct when  flowing  through  a die  is  satisfactory. 


Water  of  plasticity  . 

Shrinkage  water  . . . . 

Pore  water 

Modulus  of  rupture. 

Slaking  test,  average 
Screen  test : — 

Mesh 

Residue 

Character  of 

Per  cent 

residue 

60 

. . . 0.05 

White  mica  and  white 

sand 

80 

. . . 0.22 

White  mica  and  white 

sand 

120 

. . . 5.3 

White  sand 

200 

. . . 5.4 

White  sand 

Drying  shrinkage,  linear ; dry  length 

Volume  

Burning  test: — 

Burning 

Cone  Porosity 

Color 

shrinkage 

Total  shrinkage 

Per  cent 

Per  cent 

Per  cent 

02  35.7 

Light  cream  . . . 

...  2.1 

6.4 

1 35.2 

Light  cream  . . . 

...  2.1 

6.4 

3 32.2 

Light  cream  . . . 

...  3.3 

^Conchoidal 
) Fracture 

5 20.4 

Light  cream  . . . 

....  7.4 

11.7 

7 19.6 

Light  cream  . . . 

...  8.0 

12.3 

9 17.8 

Light  cream  . . . 

...  9.2 

13.5 

13  13.0 

Dark  gray  . . . 

...  9.7 

14.0 

Fusion  test: — It  fused  at  cones  30/31 

Summary 

The  strength  of  this  clay  is  low. 

The  percentage  of 

screen  residues  is  con- 

siderable.  Its  dryin 

g shrinkage  is 

low. 

The  total  shrinkage  at  cone  9 is  medium 

high.  It  is  not  completely  vitrified 

even 

at  cone 

13.  This 

is  a refractory  clay  and 

it  will  be  found  useful  in  the  manufacture  of  refractories. 

Sample  No.  18 

(Wm.  Ferril  pit; 

NE.  % sec.  3, 

T.  12  S.,  R.2W.) 

This  is  a soft 

white  clay  with  occasional 

yellow  discolorations.  Its  working 

property  is  good.  It  flows  satisfactorily  through  ; 

a die. 

Water  of  plasticity  . 

Shrinkage  water  . . . 

UNION  COUNTY 


63 


Pore  water  per  cent  24.6 

Modulus  of  rupture: — The  test  pieces  prepared  for  the  determination  of  its 
strength  proved  to  be  too  weak  to  be  tested. 

Slaking  test,  average min.  6 

Screen  test : — 


Mesh 

Residue 

Character  of 

Per  cent 

residue 

20 

None 

40  

Trace 

60 

04 

Fine  white  sand 

80 

0.2 

Fine  white  sand 

120 

0.7 

Fine  white  sand 

200 

0.9 

Fine  white  sand 

Drying  shrinkage,  linear  per  cent  3.1 

Volume  per  cent  12.5 


Burning 

Cone 

test : — 

Porosity 

Color 

Burning 

shrinkage 

Total 

shrinkage  Remarks 

02 

Per  cent 

40.9 

White  

Per  cent 

1.9 

Per  cent 

5.0  

3 

38.6 

White  

5.6 

8.7  

5 

36.3 

White  

6.2 

9.3  

9 

29.1 

White  

9.0 

12.1  

13 

0.05 

White  

Contains  very 

Fusion  test: — It  deforms  at  cone  33/34. 

fine  reddish 
specks 

Summary 

The  strength  of  the  clay  is  very  low.  The  percentage  of  screen  residues  is 
slight.  Its  drying  shrinkage  is  medium  low.  The  total  shrinkage  at  cone  9 is  medium. 
Vitrification  is  incomplete  even  at  cone  13.  It  is  a highly  refractory  clay.  It  is  sug- 
gested that  this  clay  will  prove  to  be  of  value  when  used  with  stronger  clays  in  the 
manufacture  of  high  grade  refractories. 

Sample  No.  22 

(Wm.  Ferril  pit;  N.E.  *4  sec.  3,  T.  12  S.,  R.  2 W.) 

This  is  a moderately  hard  clay  of  a light  gray  color.  It  has  good  working 
properties  in  the  plastic  condition  and  flows  satisfactorily  through  a die. 

Since  only  a small  sample  was  secured  for  the  preliminary  test  and  subsequent 
attempts  to  obtain  more  material  were  unsuccessful  because  the  face  of  the  pit  was 
inaccessible,  complete  test  could  not  be  made. 

The  fairly  long  period  required  for  slaking  may  indicate  a clay  of  high  bonding 
strength.  The  fusion  test  is  very  satisfactory. 

Suggested  uses : This  clay  will  be  of  value  in  the  manufacture  of  refractories 
and  possibly  of  particular  interest  to  manufacturers  of  crucibles. 

Slaking  test,  average  

Fusion  test : — It  fuses  at  cone  32. 


min.  42 


64 


ILLINOIS  FIRE  CLAYS 


MASSAC  COUNTY 
PADUCAH  POTTERY  COMPANY’S  PIT 

The  Paducah  Pottery  Company  has  a clay  pit  on  the  east  side  of  the 
Chicago,  Burlington  and  Quincy  Railroad  half  a mile  north  of  Choat,  in  the 
NE.  cor.  sec.  17,  T.  15  S.,  R.  4 E.  The  clay  body  is  lens-shaped  and  the 
accompanying  sketch  (fig.  52)  shows  the  relation  to  the  sandstone  and  gravel 
above  and  the  sandstone  below.  The  grayish- white  laminated  clay  is  14  feet  4 
inches  thick,  and  2 feet  10  inches  of  reddish  brown  clay  above  are  discarded 
with  the  overburden.  The  clay  is  loaded  at  Choat  and  shipped  to  the  plant 
at  Paducah. 

No  tests  have  been  made  to  determine  the  extent  of  the  clay. 


10  8 6 4 2 o 10 

Scale  In  feet 

Fig.  52.  Sketch  showing  the  clay  body  and  its  relations  to  the  surrounding  strata  at  the 
Paducah  Pottery  Company’s  clay  pit  north  of  Choat. 

A Soil. 

B Loess. 

C Chert  pebbles,  red  clay,  and  quartz  gravels. 

D Sandstone,  cemented  by  iron. 

E White  clay,  laminated  with  thin  sheets  of  fine  micaceous  sand. 

Shipments  vary  somewhat  as  the  clay  is  needed  at  the  pottery,  but 
averaged  in  the  spring  of  1918  from  one  to  two  cars  per  week. 

CLAYS  FROM  THE  VICINITY  OF  ROUND  KNOB 

No  clay  is  dug  near  Round  Knob  at  the  present  time,  though  formerly 
clay  was  shipped  to  potteries  at  Metropolis  and  Paducah,  and  there  is  an 
abandoned  pit  a quarter  mile  south  of  Round  Knob,  in  the  SW.  sec.  1, 
T.  15  S.,  R.  4 E.  When  operated  this  pit  furnished  three  grades  of  clay, 


MASSAC  COUNTY 


65 


white,  blue,  and  gray,  and  had  a working  face  of  8 to  10  feet.1  Another 
pit  nearby  had  7 feet  of  clay.  The  overburden  varied  in  thickness  up  to  a 
maximum  of  18  feet.  Clay  could  still  be  obtained  by  removing  a heavy 
overburden. 

A sample  was  taken  from  the  road  gutter  a half  mile  west  of  Round 
Knob,  in  the  N.  y2  SW.  sec.  8,  T.  15  S.,  R.  4 E.,  where  the  section 
is  as  follows : 


4. 

3. 

2. 

1. 


Section  half  a mile  west  of  Round  Knob 


Gravel,  rises  with  the  hill 

Clay,  red  

Clay,  white  and  pink,  sandy,  laminated ; 

pie  No.  46)  

Sand,  red  and  white  


Thickness 

Feet 

2 to  6 

4 

stains  of  iron  oxide  (sam- 

ey2 

\y2 


A report  of  the  tests  made  on  sample  No.  46  is  given  on  pages  65  and  66. 


CLAY  FROM  THE  OBERMARK  PROPERTY 

A well  is  reported  to  have  penetrated  30  feet  of  clay  on  the  C.  G.  F. 
Obermark  farm  in  sec.  36,  T.  14  S.,  R.  5 E.  A thin  sandy  horizon  lies  about 
4 feet  below  the  surface  and  streaks  of  iron  at  other  horizons.  The  clay  is 
blue-gray,  sandy,  and  of  fair  plasticity.  The  sample  (Sample  No.  47)  was 
taken  by  boring  in  a creek  bed.  Ten  acres  or  more  of  this  clay  is  available 
under  an  overburden  of  not  more  than  6 feet.  Similar  clay  has  also  been 
dug  in  sec.  6,  T.  15  S.,  R.  5 E. 

A sample  (Sample  No.  48)  was  taken  from  clay  exposed  along  the  road 
between  secs.  8 and  9,  T.  15  S.,  R.  6 E.  This  is  an  ash-colored,  sandy,  lam- 
inated clay,  interbedded  with  seams  of  limonite  and  probably  not  of  com- 
mercial value.  These  two  samples  (No.  47  and  No.  48)  were  tested  with  the 
results  given  on  pages  66  and  67. 


RESULTS  OF  TESTS 
MASSAC  COUNTY 

Sample  No.  46 

(N.  K SW.  54  sec.  8,  T.  15  S.,  R.  4 E.) 

This  is  a soft,  very  sandy  clay,  containing  much  mica.  It  is  a cream  color, 
mottled  with  brown  and  pink.  When  mixed  with  sufficient  water,  it  develops  a fair 
degree  of  plasticity  and  will  flow  through  a die  satisfactorily. 


Water  of  plasticity per  cent  22.2 

Shrinkage  water  per  cent  11.6 

Pore  water  per  cent  10.6 

Modulus  of  rupture lbs.  per  sq.  in.  217.4 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  214.0 

Slaking  test,  average min.  27 


iPurdy,  R.  C.,  and  DeWolf,  F.  W.,  Preliminary  Investigations  of  Illinois  Fire  Clay : 
111.  State  Geol.  Survey  Bull.  4,  p.  149,  1907.  See  description  of  sample  D28. 


66 


ILLINOIS  FIRE  CLAYS 


Screen  test : — 


Mesh 

20... 

40.. . 

60.. 
80. . 

Residue 
Per  cent 

2.9 

1.7 

Character  of 
Residue 

Pyrites,  sandstone  and 
mica 

Pyrites,  sandstone  and 
mica 

Mica  and  sand 

White  sand 

120... 

36.2 

White  sand 

150... 

13.5 

White  sand 

200... 

5.9 

White  sand 

Drying  shrinkage, 

linear 

Burning  test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

08 

36.7 

Light  brownish  red 

. . . . +0.5 

06 

35.4 

Light  brownish  red 

....  +0.6 

04 

35 

Light  brownish  red 

....  +0.8 

02 

36.8 

Light  brownish  red 

. ...  +0.6 

The  clay  expands  dur- 

1 

34.9 

Light  brownish  red 

....  +0.8 

ing  burning 

3 

36.5 

Light  brownish  red  

. ...  +0.6 

The  burned  pieces  are 

5 

36  3 

Darker  brownish  red  

very  weak 

7 

35.3 

Darker  with  iron  specks... 

....  +1.0 

9 

36.0 

Darker  with  iron  specks... 

....  +0.7 

11 

35.5 

Darker  with  iron  specks... 

....  +0.9 

Fusion  test: — It  deformed  at  cone  31. 


Summary 

This  is  a clay  of  medium  strength,  much  higher  than  might  be  expected  con- 
sidering its  very  sandy  character.  The  bonding  strength  is  medium.  The  percentages 
of  screen  residues  are  high.  The  drying  shrinkage  is  low.  Because  of  its  sandy 
nature,  the  clay  has  a high  and  nearly  constant  porosity  at  all  temperatures  showing 
no  sign  of  vitrification.  This  also  explains  the  reason  for  the  fact  that  it  does  not 
shrink  but  expands  slightly  at  all  temperatures. 

Suggested  uses : The  lack  of  strength  of  the  unburned  clay  will  restrict  its 
usefulness  to  admixtures  with  other  clays.  Such  sandy  clays  often  have  a distinct 
usefulness.  Because  of  its  high  fusion  test  it  should  be  of  use  in  refractories. 


Sample  No.  47 

(C.  G.  F Obermark  farm;  sec.  36,  T.  14  S.,  R.  5 E.) 

This  is  a dark  colored,  moderately  hard  clay.  It  has  a medium  plasticity  when 
mixed  with  28.5%  water  and  in  that  condition  shows  rather  poor  flowing  properties 
when  squeezed  through  a die. 

Water  of  plasticity  per  cent  25.3 

Shrinkage  water per  cent  16.0 

Pore  water  per  cent  9.3 

Modulus  of  rupture lbs.  per  sq.  in.  365.8 

Slaking  test,  average  min.  10 

Drying  shrinkage,  linear per  cent  6.8 


PULASKI  COUNTY 


67 


Burning 

test : — 

Burning 

Total 

Cone 

Porosity 

Color 

shrinkage 

shrinkage 

Per  cent 

Per  cent 

Per  cent 

02 

20.6 

Dark  cream  . . . 

3.2 

10.0 

1 

20.9 

Dark  cream  . . 

3.2 

10.0 

3 

19.6 

Cream 

3.2 

10.0 

7 

13.9 

Gray  

3.4 

10.2 

9 

7.6 

Gray  

4.4 

11.2 

10 

9.5 

Gray  

Fusion  test: — Completely  deformed  and  vesicular  at  cone  27. 


Remarks 


Conchoidal  fracture 


No  evidence  of  over- 
burning 


Summary 

This  clay  has  a medium  strength  and  medium  drying  shrinkage.  The  burning 
shrinkage  at  cone  9 is  low.  It  is  an  open  burning  clay,  which  is  incompletely  vitrified 
at  cone  10.  The  clay  is  not  refractory. 

Suggested  uses : Face  brick,  stoneware,  architectural  terra  cotta,  sanitary  ware. 


Sample  No.  48 

(Secs.  8 and  9,  T.  15  S.,  R.  6 E.) 

This  is  a gray  colored  clay,  mottled  with  brown.  It  contains  much  mica. 

Slaking  test,  average  min.  12.5 

Fusion  test: — No  deformation  at  cone  27. 

Summary 

Insufficient  material  was  received  for  complete  test.  However,  it  was  found  to 
be  a refractory  clay.  The  mode  of  occurrence  with  seams  of  limonite  will  prevent  its 
use  unless  some  method  of  purification  is  employed. 


PULASKI  COUNTY 

CLAYS  FROM  THE  VICINITY  OF  GRAND  CHAIN 

Clay  was  formerly  dug  for  pottery  near  Grand  Chain  Landing  and  re- 
cently prospect  pits  have  been  opened  at  several  places. 

On  the  O.  C.  Field  property  pits  have  been  dug  in  lenses  of  clay  in  the 
N.E  % sec.  9,  T.  15  S.,  R.  2 E.,  where  sample  No.  38,  tests  of  which  are  re- 
ported on  pages  68  and  69,  was  taken.  Both  the  bottom  and  the  top  are 
irregular,  the  top  rising  backward  into  the  hill.  A thickness  of  20  feet  of 
“black  fat”  clay  has  been  exposed  and  is  said  to  be  underlain  by  blue  and 
pink  clay.  The  overburden  of  3 feet  of  iron-cemented  sand  and  gravel 
capped  by  loess  thickens  back  over  the  ridge  to  a maximum  of  15  feet.  Clay 
has  also  been  worked  just  above  water  level  in  Ohio  River. 

J.  W.  Joynt  of  Tamms,  Illinois,  has  done  considerable  prospecting  both 
by  boring  and  pits  in  east  half  of  sec.  4 and  west  half  of  sec.  3,  T.  15  S., 
R.  2 E. 

The  clay  is  irregular  and  lenticular,  ranging  up  to  12  feet  as  a maxi- 
mum thickness.  It  is  underlain  by  sand  and  overlain  by  gravel  and  loess. 
At  pits  in  the  N.  y2  SE.  % sec.  4 the  overburden  will  average  14  to  15  feet. 
This  clay  is  white  and  resembles  the  clay  from  Mountain  Glen.  Clay  from 


68 


ILLINOIS  FIRE  CLAYS 


the  J.  B.  Hays  farm  in  the  SW.  34  sec.  3 was  of  a chocolate  color  and  con- 
tained lignite.  The  sample  No.  37  was  taken  from  a bin  which  contained 
clay  from  several  test  pits.  Results  of  tests  made  are  reported  on  pages 
69  and  70. 

A sample  of  white  to  gray  plastic  clay  was  taken  from  the  road  ditch 
two  miles  east  of  Grand  Chain,  where  clay  was  in  the  gutter.  The  sample 
was  obtained  by  boring.  The  section  is  as  follows : 

Section  2 miles  east  of  Grand  Chain 


Thickness 
Ft.  In. 

4.  Loess  16  to  32  ... 

3.  Gravel  and  red  clay  4 6 

2.  Clay,  red  1± 

1.  Clay,  white  to  gray,  plastic;  exposed  in  road  gutter 21  4 


Sample  No.  45  resampled  as  No.  1678  represents  the  upper  portion. 
Sample  No.  44  resampled  as  No.  1691  is  from  the  lower  portion  of  the 
deposit.  Results  of  tests  made  on  these  two  samples  are  presented  on 
pages  70  to  72. 

The  top  surface  of  the  clay  probably  rises  in  the  hill  and  if  so  the 
overburden  would  be  less  than  given  in  the  section.  Other  slopes  show  sand 
and  impure  clay  at  this  horizon,  proving  that  the  clay  is  lenticular  just  as  it 
is  at  other  localities. 


CLAY  FROM  CALEDONIA 

A sample,  No.  17,  was  taken  from  the  dark  gray  clay  exposed  along 
the  river  bank  at  Caledonia  (nearest  railroad  station,  Olmsted).  This 
comes  from  a 25-foot  exposure  and  is  a weathered  product  of  the  “soapstone” 
of  Midway  age. 

The  lower  14  feet  of  a section  exposed  in  the  river  bluffs  on  the  Barber 
farm,  2^4  miles  above  Caledonia,  in  sec.  13,  T.  15  S.,  R.  1 E.,  is  of  a gray, 
micaceous,  thinly  bedded  clay.  This  contains  some  lignite  and  pyrite  concre- 
tions and  is  said  to  extend  down  to  low  water  level  20  feet  below  the  bottom 
of  the  measured  section.  The  overburden  would  be  very  thick,  but  hydraulic 
stripping  would  be  possible  at  this  place.  Sample  No.  37a  (see  page  73  for 
results  of  tests)  is  from  this  horizon.  A very  plastic  white  clay  is  exposed 
about  200  yards  down  stream  at  or  near  the  water  level.  The  exposure  is 
small  and  the  quantity  uncertain. 

RESULTS  OF  TESTS 
PULASKI  COUNTY 

Sample  No.  38 

(O.  C.  Field  pit ; NE.  yA  sec.  9,  T.  15  S.,  R.  2 E.) 

This  is  a soft  shaly  material  of  a brownish  color.  It  has  good  plasticity  and 
flows  smoothly  through  the  die  when  a suitable  amount  of  water  is  added. 


PULASKI  COUNTY 


69 


Water  of  plasticity  . 
Shrinkage  water  . . . 

Pore  water 

Modulus  of  rupture 
Slaking  test  

Screen  test : — 


per  cent  38.6 

per  cent  24.6 

per  cent  14.0 

lbs.  per  sq.  in.  164.8 
min.  50 


Mesh 

Residue 

Character  of 

Per  cent 

Residue 

20 

0.27 

Rock  particles 

40 

0.25 

Rock  particles  and  sand 

80 

0.16 

Rock  particles  and  sand 

120. 

1.69 

Rock  particles  and  sand 

200 

1.52 

Rock  particles  and  sand 

Drying  shrinkage : — 

Per  cent 

Linear ; wet  length  

7.25 

Linear ; dry  length  

7.8 

Burning  test: — 

Burning 

Cone  Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04  33.4 

White  

1.8 

02 

2 

5 

9 

13 

14 


24.7 

18.1 

16.5 

14.0 

3.7 

2.8 


Cream  3.4 

Cream  6.0 

Cream  5,6 

Cream  6.0 

Stoneware  gray  7.0 

Dark  buff  exterior,  bluestoned..  6.2 


Hackly  fracture 

Hackly  fracture 
Hackly  fracture,  vitre- 
ous 

Smooth  fracture 
Appears  to  be  over- 
burned 


Fusion  test: — It  deforms  at  cone  30. 


Summary 

The  dry  clay  has  medium  low  strength.  The  amount  of  residues  left  on  the 
screens  is  low.  The  drying  shrinkage  is  medium.  The  total  shrinkage  at  cone  9 is 
medium  high.  Vitrification  is  practically  complete  at  cone  13.  It  is  a refractory 
clay  and  therefore  suitable  for  use  in  the  manufacture  of  such  wares.  The  light 
color  of  the  burned  clay  and  its  other  properties  make  it  available  for  architectural 
terra  cotta,  stoneware,  and  sanitary  ware. 

Sample  No.  37 

(Secs.  3 and  4.  T.  15  S.,  R.  2 E.) 

This  is  a soft  clay  containing  a few  nodules  of  carbonaceous  matter.  It  is  of  a 
light  gray  color.  It  flows  through  a die  fairly  satisfactorily. 


Water  of  plasticity per  cent  30 

Shrinkage  water  per  cent  21.6 

Pore  water  per  cent  8.4 

Modulus  of  rupture  lbs.  per  sq.  in.  487.2 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  249.7 

Slaking  test,  average min.  7 


70 


ILLINOIS  FIRE  CLAYS 


Screen  test : — 


Mesh  Residue  Character  of 

Per  cent  Residue 

20 Trace  

40 Trace  

60 Trace  

80 T race  

120 02  Quartz  and  mica  par- 

ticles 

200 07  Quartz  and  mica  par- 

ticles 


Drying  shrinkage  : — 

Per  cent 

Linear ; wet  length  6.6 

Linear ; dry  length  7.1 


Burning  test : — 

Cone  Porosity 

Per  cent 

2 15.9 

Color 

Cream  

Burning 

shrinkage 

Per  cent 

4.95 

Remarks 

5 

9.6 

Darker  cream 

5.7 

9 

1.7 

Gray  

10.1? 

Conchoidal 

vitreous 

fracture 

12 

.57 

5.6 

Conchoidal 

vitreous 

fracture 

uy2 

18 

Tan  exterior ; 

bluestoned  interior  4.34 

Fusion  test : — It  deformed  at  cone  28. 


Summary 

The  strength  of  the  unburned  clay  is  medium  high.  Its  bonding  strength  is 
medium.  There  is  only  a trace  of  residues  on  the  screens.  The  drying  shrinkage 
is  medium.  The  total  shrinkage  at  cone  9 is  high.  Vitrification  is  practically  com- 
plete at  cone  9.  The  sample  is  apparently  overburned  at  cone  13J-4  although  it  is 
thought  this  appearance  may  be  due  to  the  peculiar  shattering  of  the  clay  during  the 
firing.  It  is  a refractory  clay. 

Suggested  uses : For  refractories,  particularly  those  of  a dense  character  such 
as  crucibles ; also  architectural  terra  cotta,  stoneware,  and  sanitary  ware. 

Sample  No.  45  (resampled  as  No.  1678) 

(2  miles  east  of  Grand  Chain) 

This  clay  was  bored  for  samples  and  later  resampled  as  No.  1678.  This  record 
applies  to  sample  No.  1678. 

It  is  a clay  of  medium  hardness  and  a red  color.  It  develops  a good  plasticity 
when  worked  with  the  addition  of  a sufficient  amount  of  water.  When  the  plastic 
clay  is  squeezed  through  a die  it  flows  fairly  well. 


Water  of  plasticity per  cent  29.2 

Shrinkage  water  per  cent  15.3 

Pore  water  per  cent  13.4 

Modulus  of  rupture lbs.  per  sq.  in.  526.6 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  299.5 

Slaking  test  hours  2j/> 


PULASKI  COUNTY 


71 


Screen  test : — 


Mesh 

Residue 

Character  of 

Per  cent 

residue 

20 

1.0 

Brown  sandstone 

40 

Mica  and  white  sand 

60 

Mica  and  white  sand 

80 

Mica  and  white  sand 

120 

30.2 

Brown  and  white  sand 

150 

9.4 

Brown  and  white  sand 

200 

2.0 

Brown  and  white  sand 

Drying  shrinkage,  linear 

Burning 

test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Per  cent 

Per  cent 

08 

36.8 

Reddish  brown  

0.6 

06 

35.0 

Reddish  brown  

1.1 

04 

34.9 

Reddish  brown  

2.0 

02 

35.0 

Reddish  brown  

9 2 

1 

33.8 

Reddish  brown  

2.5 

3 

33.5 

Reddish  brown  

2.4 

5 

34.3 

Brown  and  black  

2.2 

7 

32.7 

Brown  and  black  

2.2 

9 

34.0 

Black 

1.9 

The  burned  pieces  are  weak. 

Fusion  test : — No.  45  deforms  at  cone  30. 

No.  1678  deforms  at  cone  28. 

Summary 

This  clay  has  a medium  high  strength  tested  alone  and  a medium  bonding  strength. 
This  is  particularly  interesting  because  the  screen  test  shows  the  presence  of  a high 
content  of  fine  grained  sand  which  does  not  impair  its  working  properties.  The  dry- 
ing shrinkage  is  medium.  It  shows  a very  open  burning  body  at  all  temperatures 
with  low  burning  shrinkages.  The  fusion  test  indicates  a refractory  clay. 

Such  open  burning  refractory  clays  having  good  plasticity  and  strength  are  of 
value  used  alone  or  in  mixtures  in  the  manufacture  of  refractory  wares. 

Sample  No.  44  [resampled  as  No.  1691] 

(2  miles  east  of  Grand  Chain) 

This  is  a soft  clay  of  a gray  color.  It  develops  a fair  degree  of  plasticity. 


Water  of  plasticity  per  cent  33.8 

Shrinkage  water  per  cent  21.4 

Pore  water per  cent  12.4 

Modulus  of  rupture lbs.  per  sq.  in.  465.6 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  325.6 

Slaking  test min.  32 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  Residue 

Trace  

Trace  Mica 

Trace  


20 

40 

60 


72 


ILLINOIS  FIRE  CLAYS 


80 Trace  

120 1.32  Mica  and  sand 

150 5.47  Mica  and  sand 

200 4.80  Mica  and  sand 


Drying  shrinkage : — 


Per  cent 

Linear ; wet  length 6.8 

Linear ; dry  length  7.0 

Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

08  31.0  Light  gray  1.45 

06  27.6  Light  gray  2.24 

04  23.2  Cream  3.81 

02  22.2  Cream  3.6 

1 17.2  Cream  4.1 

3 17.4  Cream  4.6 

5 11.5  Grayish  4.9 

7 12.3  Grayish  5.1 

9 10.4  Grayish  5.3 

11  10.9  Grayish  5.0 


Fusion  test: — It  deforms  at  cone  29. 

Summary 

This  clay  has  a medium  high  bonding  strength.  The  drying  shrinkage  is  medium. 
It  does  not  reach  a low  porosity  within  the  temperature  range  employed — up  to  cone 
11.  The  shrinkage  at  cone  9 is  medium.  It  is  a refractory  clay,  but  not  of  high 
grade.  In  addition  to  its  use  in  refractories,  it  is  of  the  type  used  for  stoneware, 
architectural  terra  cotta,  and  sanitary  ware. 

Sample  No.  17 
(River  bank  at  Caledonia) 

This  is  a clay  of  rather  hard  and  shaly  character  which  seems  to  contain  a 
considerable  quantity  of  mica.  The  clay  is  of  a brownish  color  marked  with  yellow 
specks.  It  has  rather  a poor  degree  of  plasticity  and  does  not  flow  satisfactorily 


through  a die. 

Water  of  plasticity per  cent  80.9 

Shrinkage  water  per  cent  28.1 

Pore  water per  cent  52.8 

Modulus  of  rupture lbs.  per  sq.  in.  180.9 

Slaking  test,  average min.  4 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 

10 0.25  Particles  of  clay 

14 2.2  Particles  of  clay 

20 8.8  Particles  of  clay 

35 19.5  Sand  and  clay 

48  6.3  Clay  and  flakes  of  mica 

65 4.3  Clay  and  flakes  of  mica 

100 5.0  Clay  and  flakes  of  mica 

150 4.0  Clay  and  flakes  of  mica 

200 4.1  Clay  and  flakes  of  mica 


PULASKI  COUNTY 


73 


Drying  shrinkage,  linear per  cent  5.0 

Volume  per  cent  25 


Burning  test : — 
Cone  Porosity 

Per  cent 
38.6 
38.2 
38.8 

38.6 

34.6 
34.0 


02 

1 

3 

5 

7 

9 

13 


14.8 


Color  Remarks 

Light  brown  Poorly  oxidized 

Light  brown  

Light  brown  

Darker  brown  

Darker  brown  

Black  Appears  to  show  vitri- 

fication 

Black  Overburned 


Fusion  test : — It  melts  to  a glass  below  cone  26. 


Summary 

The  strength  of  the  clay  is  medium  low.  The  percentage  of  screen  residue  is 
high.  Its  drying  shrinkage  is  medium  low.  It  appears  to  be  overburned  at  cone  13 
even  though  its  porosity  is  still  quite  high. 

The  exceptionally  high  contents  of  water  of  plasticity  and  pore  water  indicates 
a very  high  colloidal  content.  Because  of  this  the  clay  gives  erratic  results  in  the 
strength  tests.  This  deposit  has  proved  to  be  a good  grade  of  fuller’s  earth  and  a 
plant  is  in  operation  preparing  it  for  the  market. 


Sample  No.  37 a 

(Barber  farm  ; sec.  13,  T.  15  S.,  R.  1 E.) 

This  is  a light  gray  soft  clay  which  contains  many  mica  particles.  The  plastic 
mass  is  readily  molded  into  shape  and  it  flows  well  through  a die. 


Water  of  plasticity  per  cent  27.9 

Shrinkage  water  per  cent  14.9 

Pore  water  per  cent  13.0 

Modulus  of  rupture lbs.  per  sq.  in.  240.7 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  238.7 

Slaking  test,  average  min.  15 

Drying  shrinkage : — 

Per  cent 

Linear ; wet  length  3.2 

Linear  ; dry  length 3.4 

Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

2 28.80  Cream  2.6 

5 27.00  Cream  2.2 

9 3.7  Light  gray  6.1 

12  7.2  Light  gray  5.0 

13^  13.0  2.4 

Fusion  test: — Complete  fusion  at  cone  25. 


74 


ILLINOIS  FIRE  CLAYS 


Summary 

This  clay  has  medium  strength.  Its  drying  shrinkage  is  medium  low.  It  devel- 
ops a high  degree  of  vitrification  between  cones  5 and  9 with  a medium  burning 
shrinkage.  It  overburns  at  cone  12  and  is  non-refractory  since  it  fuses  at  cone  25. 

The  clay  ought  to  find  use  for  manufactures  of  stoneware,  architectural  terra 
cotta,  sanitary  ware  and  similar  wares. 


ALEXANDER  COUNTY 

CLAYS  FROM  THE  AETNA  POWDER  COMPANY’S  LAND 

Bedded  clays  are  exposed  at  several  places  on  the  land  of  the  Aetna 
Powder  Company.  High  on  the  ridge  at  the  first  separator  house,  at  least 
9 feet  of  gray  laminated  clay  has  been  exposed  in  the  excavation  for  the 
foundation.  The  clay  is  light  drab  to  gray  in  color  and  interstratified  with 
distinct  beds  of  mica  and  fine  sand.  The  section  is  as  follows : 


Section  at  first  separator  house  of  Aetna  Powder  Company  at  Fayville 

Thickness 


Feet 

3.  Loess,  with  soil  at  top 20 

2.  Gravel 1 to  2 

1.  Clay  laminated  (Sample  No.  41)  ; small  crystals  of  gypsum 9 


The  clay  could  not  be  worked  while  this  part  of  the  plant  is  in  operation. 
Results  of  tests  of  sample  No.  41,  which  was  taken  from  the  upper  5 feet, 
are  given  below. 

In  the  hollow  behind  the  old  powder  plant,  clay  is  exposed  at  several 
places.  The  section  varies  from  place  to  place,  but  the  following  is  repre- 
sentative : 


7. 

6. 

5. 

4. 

3. 

2. 

1. 


Section  behind  old  powder  plant  at  Fayville 


Soil  

Loess  

Clay  and  sand,  ash  colored 

Sand,  buff,  but  loosely  cemented  

Conglomerate  layers,  cemented  by  iron ; pebbles  up  to  3 inches 

Clay,  lignitic 

Clay,  sandy,  micaceous ; very  pure  in  places  (Sample  No.  42) . . 


Thickness 
Ft.  In. 

1 3 

.10+  .. 

4 

5 6 

1 6 

3 

4 


Most  of  this  clay  has  20  feet  or  more  of  overburden.  Results  of  the  tests 
on  Sample  No.  42  are  given  below. 


RESULTS  OF  TESTS 
ALEXANDER  COUNTY 

Sample  No.  41 

(Aetna  Powder  Company,  at  Fayville) 

This  is  a micaceous  clay  of  a gray  color  streaked  with  brown.  It  is  moderately 
hard.  When  plastic,  it  is  rather  sticky. 

Water  of  plasticity Per  cent  32.3 

Shrinkage  water  P*r  cent  21.9 


ALEXANDER  COUNTY 


75 


Pore  water  

Slaking  test,  average  

Drying  shrinkage,  linear 

Burning  test : — 

Burning 

Total 

Cone  Porosity  Color 

shrinkage 

shrinkage 

Remarks 

Per  cent 

Per  cent 

Per  cent 

02  18.9  Cream  .... 

3.9 

12.5 

Shrinkage  determined 
on  very  small  piece 

13  8.4  Gray  

3.9 

12.5 

Vitreous ; conchoidal 
fracture ; not  over- 
burned ; shrinkage 

determined  on  very 
small  piece 

Fusion  test : — Y deformed  at  cone  25.  The  cone  appears  to  have  developed  a decided 
vesicular  structure. 

Summary 

A very  plastic  and  rather  sticky  clay,  which  has  a medium  drying  shrinkage.  It 
has  a medium  porosity  at  cone  02  and  is  still  quite  porous  at  cone  13  with  a medium 
high  shrinkage.  Its  fusion  point  is  about  cone  25,  which  places  it  amongst  the  non- 
refractory clays. 

The  incomplete  tests  indicate  a clay  which  may  be  suited  for  stoneware,  sanitary 
ware,  or  similar  wares. 


Sample  No.  42 

(Aetna  Powder  Company  at  Fayville) 


The  clay  is  a uniform  light  gray  in  color.  It  is  rather  hard.  When  tempered 
with  water  it  has  a fair  degree  of  plasticity  and  flows  through  a die  satisfactorily. 

Water  of  plasticity per  cent  29.1 

Shrinkage  water  per  cent  15.4 

Pore  water  per  cent  13.6 

Modulus  of  rupture lbs.  per  sq.  in.  283.1 

Slaking  test,  average  min.  10 

Drying  shrinkage,  linear  7.5 

Burning  test : — 


Total 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

12.8 

Cream 

13.7 

Hackly  fracture,  vitre- 

ous 

5 

1.3 

Gray  

16.0 

9 

0.0 

Gray  

17.5 

13 

0.0 

17.5 

Fusion  test : — Cone  down  at  cone  25.  No  vesicular  structure  seems  to  have  been  de- 
veloped in  the  cone. 


Summary 

The  clay  has  a medium  strength.  Its  linear  shrinkage  is  medium.  The  total 

shrinkage  at  cone  9 is  high.  Practically  complete  vitrification  is  reached  at  cone  5 
and  there  are  no  signs  of  overburning  at  'Cone  13.  It  is  a non-refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  and  face- 

brick 


76 


ILLINOIS  FIRE  CLAYS 


CLAYS  OF  PENNSYLVANIAN  AGE 

Field  and  Laboratory  Notes  on  Pennsylvanian  Clays 

Field  notes  by  C.  R.  Schroyer 
Tests  by  C.  W.  Parmelee 


MONROE  COUNTY 

Clay  outcrops  in  St.  Clair  County  along  a small  creek  that  flows  south- 
west in  the  SW.  yf\  sec.  22,  T.  1 S.,  R.  10  W.  The  clay  is  at  the  base  of 
the  Pennsylvanian  system,  specifically  at  the  Cheltenham  horizon.  At  the 
outcrop  it  is  mottled  yellow  and  white,  plastic,  and  comparatively  free  from 
sand.  Borings  show  that  the  yellow  color  is  restricted  to  the  upper  part 
where  there  is  an  overburden  of  gravel  and  glacial  drift. 

Section  of  clay  1 mile  south  of  Columbia 


Thickness 
Ft.  In. 

5.  Overburden,  clay  and  gravel  0 to  20  .. 

4.  Clay,  yellow  and  white  (by  boring)  10  8 

3.  Clay,  white,  exposed  in  bank  of  creek 2 

2.  Clay;  boring  in  bed  of  creek  (Sample  No.  61) 3 6 

1.  Limestone,  Mississippian 


The  slope  above  the  creek  has  slumped  and  it  is  uncertain  if  this  thick- 
ness of  16  feet  2 inches  represents  the  maximum  thickness  of  the  clay,  which 
is  exposed  for  320  feet  along  the  stream.  A well  28  feet  in  depth  ended  in 
loose  sand  less  than  a quarter  of  a mile  east  of  the  outcrop.  Other  wells 
which  should  have  reached  the  clay  if  it  were  a persistent  bed,  have  not 
revealed  it  elsewhere. 

The  quantity  of  this  clay,  though  apparently  small,  is  probably  sufficient 
so  that  development  for  use  as  a blend  with  other  clays  might  be  considered. 
It  is  at  the  horizon  of  the  Cheltenham  clay  of  the  St.  Louis  district.  Sample 
No.  62  was  taken  from  a boring  which  penetrated  the  entire  thickness. 

RESULTS  OF  TESTS 
MONROE  COUNTY 

Sample  No.  61 
(1  mile  south  of  Columbia) 

This  is  a medium  hard,  grayish-colored  clay,  mottled  with  dark  brown.  It  has 

a medium  hardness.  When  tempered  with  water  it  becomes  very  plastic. 


Water  of  plasticity  per  cent  33.5 

Shrinkage  water per  cent  20.5 

Pore  water  per  cent  13 

Modulus  of  rupture,  average lbs.  per  sq.  in.  567 

minimum  lbs.  per  sq.  in.  420 

maximum  lbs.  per  sq.  in.  773 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  372.7 

Slaking  test,  average min.  16 

Drying  shrinkage,  linear  per  cent  8.4 


PENNSYLVANIAN  CLAYS 


77 


Screen  test : — 


Mesh 

20 

Residue 
Per  cent 

T race 

Character  of 
residue 

35. . 

Trace 

60.. 

0.32 

Colored  sand 

120... 

0.3 

Colored  sand 

200.. 

Colored  sand 

Burning  test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

1.5 

Tan  

7.6 

Hackly,  vitreous 

2 

0.6 

Tan  

7.4 

Hackly,  vitreous 

5 

1.6 

Tan  

6.9 

Vitrified,  hackly 

9 

6.1 

Tan  

6.3 

Overburned 

13 

7.0 

Dark  tan  

Overburned 

Fusion  test : — Complete  fusion  before  cone  26. 

Summary 

This  clay  has  an  exceptionally  good  strength  when  tested  alone,  but  only  medium 
when  mixed  with  standard  sand.  It  is  very  free  from  all  particles  coarser  than  200 
mesh.  The  drying  shrinkage  is  medium.  It  develops  a high  degree  of  vitrification 
at  an  exceptionally  low  temperature  and  overburns  at  cone  5.  It  is  completely  fused 
before  cone  26  is  reached  and  therefore  is  a non-refractory  clay. 

This  clay  will  probably  be  most  useful  for  the  manufacture  of  brick  and  blocks, 
etc.,  for  building  purposes,  and  possibly  pavers. 


Sample  No.  62 
(1  mile  south  of  Columbia) 

The  sample  borings  are  a gray  color,  mottled  with  yellow, 
a suitable  quantity  of  water,  the  clay  becomes  very  plastic. 

Water  of  plasticity  

Shrinkage  water  

Pore  water 

Slaking  test,  average 

Drying  shrinkage,  linear 

Burning  test : — 


When  mixed 

per  cent 

per  cent 

per  cent 

min. 

per  cent 


with 

38.9 

22.9 

15.9 
8 

8.5 


Cone 

Porosity 

Color 

Burning 

shrinkage 

Total 

shrinkage 

Remarks 

02 

Per  cent 

1.5 

Terra  cotta  . . . . 

Per  cent 

....  3.7 

Per  cent 

11.2 

Vitrified 

1 

1.8 

Light  brown  . . . 

. . . . 4.0 

12.5 

Vitrified 

5 

0.7 

Reddish  brown  . 

Vitrified  conchoidal 

9 

5.0 

Reddish  brown  . 

6.5 

fracture 

Overburned 

13 

8.5 

Reddish  brown  . 

Vesicular 

1J  O.U  I\CUUIMI  

Fusion  test : — Completely  fused  at  cone  27,  vesicular. 


Summary 

This  is  a non-refractory  clay  which  vitrifies  at  a very  low  temperature  and  over- 
burns between  cones  5 and  9.  Its  drying  shrinkage  is  medium.  Burning  shrinkage  at 
cone  1 is  high. 

It  is  suited  for  use  in  the  manufacture  of  building  brick  and  common  wares. 


78 


ILLINOIS  FIRE  CLAYS 


MADISON  COUNTY 

“The  outcrop  of  the  fire  clay  in  Madison  County  extends  from  a point 
on  the  county  line  north  of  Godfrey  southerly  and  easterly  to  East  Alton. 
South  of  East  Alton  it  is  cut  ofif  by  the  alluvium  of  the  Mississippi  River 
bottom.  Fire  clay  is  found,  however,  two  miles  east  of  Collinsville  at  Cantine 
at  a depth  of  270  feet,  and  it  seems  probable  in  view  of  the  extent  of  the  fire 
clay  into  the  St.  Louis  district,  that  it  may  be  found  underlying  the  entire 
county.”1 

This  clay  is  used  for  sewer  pipe  by  the  East  Alton  Stoneware  Pipe 
Company  at  their  plant  \l/2  miles  northeast  of  East  Alton. 


Section  of  the  Stoneware  Pipe  Company’s  shaft  at  East  Alton  in  the 

NE.  % sec.  15,  T.  5 N.,  R.  9 IV. 


7. 

6. 

5. 

4. 

3. 


2. 


1. 


Shale,  light  colored  ; flint  concretions  and  nodules  of  calcareous 

ironstone 

Shale,  black;  “slate”  of  miners 

Coal  (No.  2)  

Clay,  “little  vein”  

Limestone;  hard,  flinty,  brecciated  beds 

Green  shale — 3 in. 

Dark  shale — 2 in. 

Fireclay  Coal — 1 in. 

Light  colored  fireclay — 3 ft.  (Sample  No.  59) 

Dark  clay,  colored  by  carbon — 11  ft.  (Sample  No.  60) 
Sandstone,  brown,  below  


Thickness 
Ft.  In. 

50 

1 6 

2 3 

4 
7 


14  6 


Only  the  upper  2 y2  to  3 feet  of  the  dark  clay  and  the  3 feet  of  light 
clay  are  used  for  sewer  pipes.  The  lower  beds  run  high  in  sulphur  and 
contain  large  amounts  of  pyrite.  These  lower  beds  are  variable  in  thickness 
and  in  places  missing,  so  that  the  total  thickness  is  not  over  six  feet.  At 
the  old  mines  in  the  NW.  sec.  15  the  thickness  is  reported  to  have  been 
about  seven  feet. 


RESULTS  OF  TESTS 
MADISON  COUNTY 

Sample  No.  59 

(Stoneware  Pipe  Company’s  shaft;  NE.  % sec.  15,  T.  5 N.,  R.  9 W.) 

A very  hard,  dark  gray  colored  clay  which  develops  a good  plasticity  although 
a little  sticky.  It  flows  satisfactorily  through  a die  when  rather  soft. 

Water  of  plasticity per  cent  36.2 

Shrinkage  water  per  cent  24.0 

iLines,  Edwin  H.,  The  Pennsylvanian  fire  clays  of  Illinois : 111.  State  Geol.  Survey 

Bull.  30,  p.  66,  1917. 


MADISON  COUNTY 


79 


Pore  water 

Modulus  of  rupture  

With  50%  standard  sand — Modulus  of  rupture 

Slaking  test  

Screen  test : — 

Mesh  Residue 

Per  Cent 

40 17 

60 4.57 

80 1.05 

120 6.76 

150 1.4 

200 1.44 

Drying  shrinkage : — 


Linear ; wet  length 
Linear ; dry  length 


Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

2 3.4  Grayish  white  6.3 

5 2.4  6.6 

9 5.4  Tan  exterior  5.7 

12  14.2  Red  tan  exterior,  bluestoned  in- 

terior   3.4 

13  11.9  2.3 

15  10.0  Buff  bluestoned 2.9 


Oxidation  conduct: — Very  difficult  to  oxidize. 
Fusion  test : — Down  at  cone  28. 


per  cent  12.2 

lbs.  per  sq.  in.  589.0 
lbs.  per  sq.  in.  169.8 
hours  6 


Character  of 
residue 

Pyrites 

Pyrites,  hard  particles 
of  clay  and  fine  sand 

Pyrites,  fine  sand,  and 
clay 

Pyrites,  sand,  and  clay 

Pyrites,  mica,  fine  sand, 
mostly  clay 

Mica,  fine  sand  and  clay 


Per  cent 
. 9.72 
. 10.5 


Remarks 


Black  core 
Black  core 


Large  iron  slag  spots 


Summary 

A clay  which  has  medium  high  strength  when  tested  without  admixture  of  sand 
but  shows  a medium  low  bonding  power.  It  contains  a notable  amount  of  mineral 
particles  which  are  retained  upon  the  screens.  The  presence  of  pyrite  amongst  these 
explains  the  slag  spots  formed  at  high  temperatures  as  well  as  the  pitted  and  vesicular 
appearance  of  the  fusion  test.  Undoubtedly  this  clay  can  be  greatly  improved  by 
washing.  The  drying  shrinkage  is  medium  high  and  the  burning  shrinkage  at  cone  9 
is  medium  high.  Its  low  porosity  at  cone  2 is  unusual.  The  overburning  which  de- 
velops between  cones  9 and  12  is  undoubtedly  due  to  the  high  carbon  and  sulphur 
content.  It  is  a difficult  clay  to  oxidize. 

It  is  thought  that  the  purification  of  this  clay  by  washing  will  greatly  improve 
its  properties  and  extend  its  usefulness ; otherwise,  it  will  be  very  difficult  to  use 
because  of  its  high  carbon-sulphur  content  and  consequent  slow  oxidation. 


80 


ILLINOIS  FIRE  CLAYS 


Sample  No.  60 

(Stoneware  Pipe  Company’s  shaft;  N.E. x/^  sec.  15,  T.  5 N.,  R.  9 W.) 

The  sample  is  a dark  brown  clay,  having  a flinty  hardness.  Its  plasticity  is  good 
although  it  is  slightly  sticky.  When  it  has  rather  a soft  consistency,  it  flows  well 
through  a die. 

Water  of  plasticity  per  cent  3.3.05 

Shrinkage  water  per  cent  23.05 

Pore  water per  cent  10.0 

Modulus  of  rupture lbs.  per  sq.  in.  427 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  164.5 


Slaking  test  . . 
Screen  test : — 


hours 


Mesh 

Residue 

Character  of 

Per  cent 

residue 

60 

Particles  of  sand 

80 

100 

0.16 

Fine  sand 

150 

0.17 

Fine  sand  and  organic 

matter 

200 

0.15 

Fine  sand  and  organic 

matter 


Drying  shrinkage 


Pet  cent 

Linear ; wet  length  8.72 


Linear ; dry  length 
Burning  test: — 

Cone 


2 

5 

9 

12 

13 


9.3 


Burning 

Total 

Porosity 
Per  cent 

Color 

shrinkage 

Per  cent 

shrinkage 
Per  cent 

Remarks 

2.45 

Red  

7.28 

15.5 

Vitreous 

1.5 

Grayish  

7.3 

Black  core 

0.7 

Gray  exterior  

7.4 

Black  core 

2.6 

Tan  exterior ; bluestoned . . 

7.8 

3.8  

>t : — Cone  31 — bloated. 

6.1 

Overburned 

Summary 

This  clay  is  similar  in  some  respects  to  sample  No.  59.  Its  bonding  strength  is 
medium  low  although  the  pure  clay  has  a considerably  higher  modulus  of  rupture. 
It  contains  very  little  material  too  coarse  to  pass  a 200-mesh  sieve.  The  drying 
shrinkage  is  medium  high.  The  burning  conduct  is  of  particular  interest  because  of 
the  low  porosity  reached  at  a low  cone  (2)  and  maintained  over  a wide  range  of 
temperature.  There  are  some  slight  indications  of  overburning  above  cone  12.  The 
presence  of  a black  core  at  cones  5 and  9 indicates  that  care  will  be  required  in 
oxidizing  this  clay  during  burning. 

Suggested  uses : Its  property  of  burning  dense  at  a low  temperature  and  main- 
taining a wide  vitrification  range  ought  to  make  it  desirable  for  vitrified  or  close 
bodies.  It  may  possibly  serve  for  pavers  although  the  poor  oxidation  conduct  may 
prevent  this.  It  is  being  used  for  sewer  pipe  and  probably  would  serve  for  conduits. 
The  color  of  the  burned  clay  is  not  satisfactory  for  stoneware.  It  may  possibly  be 
used  for  architectural  terra  cotta. 


CALHOUN  COUNTY 


81 


CALHOUN  COUNTY 

Formerly  a plant  at  Golden  Eagle  manufactured  fire  brick  from  the 
clay  lying  directly  below  the  No.  2 coal.  The  mines  are  in  bad  condition 
(fig.  53)  and  no  measurement  of  the  clay  could  be  made.  Five  feet  of  the 
upper  part  of  the  seam  was  mined.  At  the  bottom  of  this  level  are  nodular 
limestone  boulders  full  of  pyrite  crystals.  Smaller  boulders  were  found 
scattered  through  the  clay.  The  sample  No.  58  was  taken  from  a pile  of 
clay  which  had  been  dug  several  years  previous.  However  this  clay  was 
still  unslacked  and  appeared  fresh  and  in  good  condition. 


Fig.  53.  Abandoned  fire  clay  pit  at  Golden  Eagle. 

The  area  underlain  by  this  clay  is  small,  but  with  the  present  equipment 
might  again  justify  operation.  Directly  above  the  clay  is  a two-foot  coal 
bed  which  is  mined  with  it.  Transportation  is  entirely  by  water. 

RESULTS  OF  TESTS 
CALHOUN  COUNTY 

Sample  No.  58 

(Abandoned  plant  at  Golden  Eagle) 

This  is  a very  hard  grayish  colored  clay  which  contains  much  finely  divided 
pyrite.  Upon  the  addition  of  a suitable  amount  of  water  it  develops  a good  but 
sticky  degree  of  plasticity.  It  slakes  very  slowly. 


Water  of  plasticity per  cent  34.4 

Shrinkage  water  per  cent  25.5 

Pore  water per  cent  18.9 

Modulus  of  rupture lbs.  per  sq.  in.  165.7 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  124.6 

Slaking  test  hours  5 y2 


82 


ILLINOIS  FIRE  CLAYS 


Screen  test : — 


Mesh  Residue  Character  of 

Per  cent  residue 

120 50  Pyrites,  fine  sand  and 

particles  of  sand 

150 09  Mica  and  sand 

200 12  Pyrites,  sand,  clay  and 

organic  material 


Drying  shrinkage : — 


Per  cent 


Linear;  wet  length  10.05 

Linear;  dry  length  11.6 


Burning  test : — 


Burning 


Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

10.0 

6.1 

5 

5.2 

Tan  

6.0 

Small  black  core 

9 

7.0 

Buff 

4.3 

Black  core,  fine  iron 

12 

5.0 

Buff  exterior  ; bluestoned. . , 

5.0 

spots 

13 

7.0 

2.6 

Flashed 

15 

5.5 

Buff;  bluestoned  

2.8 

Overburned 

Fusion  test: — Cone  Ys  deformed  at  cone  26.  The  cone  has  a vesicular  structure. 


Summary 

This  clay  has  a medium  low  strength  and  a medium  low  bonding  strength.  The 
drying  shrinkage  is  medium  high.  The  effect  of  the  small  residue  of  finely  divided 
pyrite  becomes  evident  at  the  higher  temperatures,  especially  in  the  fusion  test. 
Washing  the  clay  for  some  products  will  correct  this.  The  poor  oxidation  conduct 
should  be  noted.  The  clay  is  on  the  border  line  between  a non-refractory  and  a 
refractory  material.  The  test  piece  has  the  appearance  of  having  been  overfired  at 
cone  15. 

Suggested  uses : Architectural  terra  cotta,  face  brick. 

GREENE  COUNTY 

At  White  Hall,  Greene  County,  fireclay  has  long  been  dug  for  use  in 
the  manufacture  oPsewer  pipe,  and  stoneware  and  refractory  clay  has  been 
shipped  widely  from  the  pits  at  Drake. 

Two  miles  southeast  of  Hillview  in  the  S.  sec.  34,  T.  12  N.,  R.  13 
W.,  a small  amount  of  clay  has  been  recovered  from  above  the  Mississippian 
limestone.  This  is  probably  a residual  clay  from  the  decay  of  the  limestone 
and  if  so,  does  not  properly  belong  in  the  Pennsylvanian  system. 

The  clay  has  a greenish  or  bluish  white  color  when  wet,  but  whitens 
upon  drying.  The  exposed  part  contains  abundant  cherty  and  calcareous 
nodules,  and  gritty  calcareous  sand.  The  thickness  may  locally  be  as  much 
as  10  feet  but  the  distribution  is  irregular  and  pockety,  conforming  as  it  does 
into  the  irregular  surface  of  the  underlying  weathered  limestone. 


GREENE  COUNTY 


83 


Section  of  the  small  opening  in  S.]/2sec.34,  T.12N.,  R.13W. 

Thickness 

Feet 


4.  Loess  and  soil  10  =*= 

3.  Gravel 2 

2.  Clay,  blue,  containing  calcareous  sand  and  small  gravel ; traces  of 

pink  (Sample  No.  57) 3 

1.  Limestone,  residual,  decomposed,  and  cherty;  covered  at  base  but 

underlain  by  bedded  limestone  further  down  the  ravine 12 


The  extent  of  this  clay  is  uncertain,  but  it  has  been  found  in  nearby 
wells  to  the  west.  A few  carloads  have  been  dug  from  the  slope  above  the 
limestone  one  mile  west  of  this  outcrop  where  a boring  is  said  to  have  pene- 
trated 9 feet  of  clay.  The  results  of  the  tests  made  on  sample  No.  57  are 
given  on  pages  84  and  85. 

The  overburden  would  range  from  15  to  35  feet,  depending  upon  how 
far  the  working  penetrated  the  divides. 

Washing  would  be  necessary  to  make  this  clay  suitable  for  use  as  a 
refractory. 

The  results  of  the  tests  made  on  sample  No.  55  which  is  from  the  E.  N. 
Ford  farm  near  Hillview,  are  given  on  pages  85  and  86. 

Clay  has  not  been  shipped  from  Drake  for  over  two  years.  Previous 
to  that  time  it  had  been  shipped  more  widely  than  any  other  in  Illinois.  The 
greatest  thickness  of  clay  ever  dug  was  26  feet.  A well  penetrated  8 feet 
of  clay  below  this.  As  both  the  top  and  bottom  are  irregular,  the  thickness  is 
variable  and  becomes  as  little  as  5 feet.  An  eighth  of  a mile  south  of  the 
station  it  is  20  feet  thick. 

The  overburden  varies  from  10  to  40  feet,  a thickness  that  makes  the 
working  of  the  old  pit  unprofitable. 

The  clay  has  an  Indian  red  color  locally,  especially  near  the  top  of  the 
west  pit,  which  renders  the  clay  useless  for  refractory  purposes. 

Clay  is  also  reported  from  north  of  the  railroad  at  Drake,  where  a well 
section  was  given  as  follows: 


Log  of  well  north  of  Drake 


Description  of  strata 

“Earth” 

Not  described  

Sandstone 

Clay  

Limestone  


Thickness 

Depth 

Ft. 

Ft. 

...  12 

12 

...  8 

20 

...  7 

27 

...  15 

42 

Sample  No.  136,  sent  in  by  Mr.  A.  M.  Cain,  was  taken  from  a shallow 
pit  north  of  the  railroad.  Sample  No.  54  was  taken  from  the  lower  clay; 
sample  No.  56  from  the  upper  clay,  34  mile  south  of  Drake.  Sample  No. 
53  from  the  farm  of  C.  T.  Hicks,  34  mile  south  of  Drake.  The  results  of 
tests  on  these  samples  are  given  on  pages  86  to  90. 


84 


ILLINOIS  FIKE  CLAYS 


Section  of  clay  pits  east  of  White  Hall 

Thickness 
Ft.  In. 


6.  Soil  and  yellow  underlying  hardpan 3 

5.  Clay,  yellow,  and  till 16 

4.  Shale  and  clay,  sandy;  stringers  of  gravel 17  5 

3.  Clay,  buff  and  white  (Sample  No.  49) 3 5 

2.  Clay,  bluish  with  scattered  purplish  red  and  dark  stains  (Sample 

No.  52)  7 6 

1.  Partly  covered  to  deepest  part  of  pit;  clay  not  now  worked 3 6 


The  clay  above  as  well  as  that  below  is  used  entirely  for  sewer  pipe 
and  stoneware  by  the  White  Hall  Sewer  Pipe  and  Stoneware  Company  at 
their  plant  in  White  Hall.  Results  of  tests  on  samples  No.  49  and  No.  52 
are  given  on  pages  90  to  92. 


6. 

5. 

4. 

3. 

2. 

1. 


Section  2x/2  miles  northeast  of  White  Hall 


Drift 

Shale,  local  

Coal  (No.  2)  

Clay,  yellow,  sandy  

Clay,  white  and  buff  (Sample  No.  51) 

Clay,  bluish ; iron  concretions  in  places ; used  for  sewer  pipes 
(Sample  No.  50) 


Thickness 
Ft.  In. 

12 

1 10 

2 6 

4 
6 

17  6 


The  results  of  tests  made  on  samples  No.  51  and  No.  50  are  given  on 
pages  92  to  94.  Lines1  says  of  this  area:  “It  is  reported  * * * that 
good  deposits  extending  another  mile  east  are  available  when  the  present  pits 
are  worked  out.  The  dip  of  the  rocks  here  is  easterly,  and  nothing  is  known 
of  the  clay  after  it  gets  below  drainage,  but  it  is  possible  that  shafts  would 
reach  the  clay  over  a large  area.” 


RESULTS  OF  TESTS 
GREENE  COUNTY 

Sample  No.  57 

(S.  sec.  34,  T.  12  N.,  R.  13  W.) 

The  sample  is  a gray  colored  clay  stained  with  yellow  and  containing  a few 
black  spots.  When  tempered  with  water  it  is  very  plastic. 


Water  of  plasticity per  cent  25.9 

Shrinkage  water  per  cent  14.9 

Pore  water per  cent  11.0 

Modulus  of  rupture lbs.  per  sq.  in.  565. 5 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  370 

Slaking  test,  average min.  9 

Drying  shrinkage,  linear  per  cent  7.0 

Volume  per  cent  27.6 


iLines,  Edwin  H.,  Pennsylvanian  fire  clays  of  Illinois:  111.  State  Geol.  Survej’  Bull.  30, 
p.  67,  1914. 


GREENE  COUNTY 


85 


Burning  test : — 


Cone 

02 

Porosity 
Per  cent 
12.9 

Color 

Gray  

Burning 

shrinkage 

Per  cent 

12.5 

Remarks 

1 

18.9 

Cream  

11.1 

3 

1.5 

Dark  gray  

12.5 

Vitreous  conchoidal 

5 

0.3 

Dark  gray  

13.1 

fracture 

7 

0.4 

Dark  gray  

12.5 

Glassy  fracture 

9 

0.6 

Dark  gray  

12.1 

Glassy  fracture 

13 

0.6 

Dark  gray  

11.7 

Glassy  fracture 

Small  particles  of  some  more  fusible  mineral  are  scattered  through  the  mass. 


Note: — Grayish  color  of  cone  3 et  seq.  may  be  due  to  reduction. 

Fusion  Test : — Fused  completely  at  cone  26. 

Summary 

The  strength  of  the  unburned  clay  is  medium  high  and  the  bonding  strength  is 
medium.  The  drying  shrinkage  is  medium  and  at  cone  9,  the  total  shrinkage  is 
medium.  The  test  pieces  were  virtually  non-porous  at  cone  3 and  showed  no  signs 
of  overburning  at  cone  13,  indicating  a very  long  range  of  vitrification.  It  is  not  a 
refractory  clay. 

Suggested  uses:  The  very  satisfactory  strength  tests  together  with  the  early 

vitrification  and  long  heat  range  suggest  a clay  useful  for  stoneware,  architectural 
terra  cotta,  sewer  pipe,  and  paving  brick.  The  rapid  rate  of  vitrification  between  cones 
1 and  3 may  prove  to  limit  its  usefulness. 


Sample  No.  55 

(E.  N.  Ford  farm,  near  Hillview) 

This  clay  is  colored  brown  mottled  with  gray.  It  contains  numerous  lumps  of 
limestone  varying  in  size  from  a small  grain  to  a hazel  nut.  The  clay  tempered  with 
water  has  good  plasticity  but  is  slightly  sticky  if  too  wet.  Its  conduct  when  squeezed 
through  a die  is  fair. 

Water  of  plasticity  per  cent  39.5 

Shrinkage  water per  cent  25.4 

Pore  water per  cent  14.1 

Modulus  of  rupture lbs.  per  sq.  in.  172.5 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  145.17 

Slaking  test,  average min.  55 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 

40 25  Light  colored  particles, 

few  sand  grains 

60 97  Light  colored  particles, 

few  sand  grains 

80 23  More  fine  sand 

120 42  Light  particles  and  fine 

sand 

150 18  Light  and  colored 

200 07  Fine  sand,  mica,  light 

and  hard  particles 


86 


ILLINOIS  FIRE  CLAYS 


Drying  shrinkage : — 

Per  cent 


Linear ; wet  length  6.05 

Linear ; dry  length  7.52 

Volume  25.0 


Burning  test : — 


Burning 


Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

2.19 

Very  light  tan 

9.58 

5 

0.5 

Very  light  tan 

9.58 

9 

3.3 

Gray 

9.78 

Vitreous  fracture 

12 

4.62 

Gray  with  iron  spots 

8.4 

Small  light  red  iron 

spots  slagged  in  the 

piece 

13 

9 0 

6.3 

Fusion  test : — Deforms  at  cone  29. 

Summary 

This  is  a clay  of  a medium  low  strength  and  medium  low  bonding  strength. 
It  has  only  a slight  amount  of  screen  residues  coarser  than  a 200  mesh.  The  drying 
shrinkage  is  medium.  It  is  practically  non-absorbent  at  cone  2 and  overburns  be- 
tween cones  5 and  9.  The  shrinkage  at  cone  9 is  high.  Although  the  test  cone  did 
not  deform  until  cone  29  was  reached,  yet  there  were  numerous  slag  spots  indicating 
advanced  stages  of  fusion  in  local  areas. 

Suggested  uses:  Face  brick,  sewer  pipe  (?),  paving  brick  (?),  architectural 
terra  cotta,  sanitary  ware. 


Sample  No.  136 
(A.  M.  Cain;  near  Drake) 


This  sample  is  a sandy,  hard  clay  of  a light  gray  color,  mottled  with  brown. 
It  has  a medium  plasticity  and  is  inclined  to  be  sticky.  When  forced  through  a 


die  it  flows  satisfactorily. 

Water  of  plasticity  per  cent  25.6 

Shrinkage  water  per  cent  14.9 

Pore  water per  cent  10.7 

Modulus  of  rupture lbs.  per  sq.  in.  586 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  376 

Slaking  test,  average  min.  28 


Screen  test : — 


Mesh  Residue  Character  of 

Per  cent  residue 

20 5.31  Quartz  particles 

40 39  Quartz  particles 

60 1.67  Quartz  particles 

80  55  Quartz  particles,  white 

and  brown 

120 3.76  Quartz  particles 

200 2.96  Quartz  particles,  most- 

ly brown 


GREENE  COUNTY 


87 


Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  9.5 

Linear;  wet  length  10.7 

Volume  28.8 

Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

04  24.7  Salmon  -|-0.65 

02  25  Red  brown  -|-0.8 

2 23.7  Red  brown 0.2 

5 23  Red  brown  1.4 

9 20  Chocolate  1.5 

13  21  Chocolate  3.1 


Fusion  test: — Completely  deformed  at  cone  25. 

Summary 

This  clay  has  a medium  high  strength,  tested  alone,  but  its  bonding  strength  is 
medium.  It  contains  a considerable  amount  of  quartz  sand.  The  drying  shrinkage 
is  medium  high.  The  total  shrinkage  at  cone  9 is  medium.  The  burning  shrinkages 
at  all  temperatures  are  low.  In  fact,  there  is  a slight  swelling  at  temperatures  up 
to  cone  1.  The  clay  is  open  burning  since  its  porosities  are  high  at  cones  5 and  above. 
It  is  non-refractory. 

It  is  suited  best  for  brick  and  similar  products  having  a dark  color  and  high 
porosity. 


Sample  No.  54 
mile  south  of  Drake) 


This  is  a soft  clay  of  a light  gray  color  mottled  strongly  with  darker  gray  and 
occasional  brown  spots.  After  the  addition  of  a suitable  amount  of  water  it  de- 
velops good  plastic  properties  and  flows  fairly  well  through  a die. 


Water  of  plasticity  per  cent  24.5 

Shrinkage  water  per  cent  11.7 

Pore  water  per  cent  12.8 

Modulus  of  rupture lbs.  per  sq.  in.  250 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  220 


Screen  test: — 

Mesh  Residue  Character  of  residue 

Per  cent 

20 0.13  Roots  and  rock  parti- 

cles 

40 0.03  Roots  and  rock  parti- 

cles 

60 015  Quartz  sand 

80 0.03  Quartz  sand 

120 0.54  Quartz  sand,  and  mica 

200 »• 4.2  Quartz  sand,  and  mica 


88 


ILLINOIS  FIRE  CLAYS 


Drying  shrinkage : — 


Linear ; dry  length  

Linear ; wet  length  

Volume  

Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage 

Percent  Percent 

02  22  White  

1 22  White  

3 21  Light  cream  2.8 

5 20  Light  cream  3.5 

6 19  Light  cream 3.9 

8 16  Dark  cream 4.1 

12  7.6  Cream,  bluestoned  slightly 5.7 

13  4.0  Light  tan  exterior,  bluestoned...  5.8 

15  4.0  Tan  exterior,  bluestoned 6.9 

Fusion  test: — Deforms  at  cone  29. 


Per  cent 
..  5.7 
..  5.4 
. . 24.1 


Remarks 


Earthy  fracture,  vana- 
dium? stain 


Earthy  fracture,  vana- 
dium? stain,  slight 
iron  stain 

Earthy  fracture,  vana- 
dium? stain,  slight 
iron  stain 


Summary 

This  is  a clay  having  medium  bonding  strength.  The  drying  shrinkage  is  me- 
dium. It  contains  very  little  material  coarser  than  a 200  mesh.  The  burning  shrink- 
age at  cone  8 is  medium.  Samples  burned  up  to  and  including  cone  8 have  quite  a 
high  porosity.  This  decreases  rapidly  between  cones  8 and  12.  It  is  a refractory 
clay. 

Possible  uses : Architectural  terra  cotta,  sanitary  ware,  stoneware,  face  brick,  as 
a bond  clay  in  refractories. 


Sample  No.  56 
04  south  of  Drake) 

A medium  soft  clay  colored  light  gray,  with  brown  stains  and  containing  a few- 
black  nodules.  When  tempered  with  water  it  is  very  plastic  and  flows  well  through 
a die. 

Water  of  plasticity  per 

Shrinkage  water  per 

Pore  water  

Modulus  of  rupture  lbs. 

With  50%  standard  sand — Modulus  of  rupture lbs. 

Slaking  test,  average  min. 

Screen  test : — 

Mesh  Residue 

Per  cent 

20 0.3 


21.2 

10.1 

11.1 

462 

231.8 

14 

Character  of  residue 


40. 


Rootlets  and  rock  par- 
ticles 

0.12  Rootlets  and  quartz 
grains 


GREENE  COUNTY 


89 


60 


0.33 


80 0.08 

120 3.42 


200 

Drying  shrinkage : — 


8.59 


Linear;  dry  length 
Linear;  wet  length 

Volume  

Burning  test: — 


Cone  Porosity 
Per  cent 

1 23 

2 20 

3 21.4 

6 19 


Color 

Cream  

Cream  

Light  cream 
Light  cream 


Burning 
shrinkage 
Per  cent 
. . 2.2 
...  2.5 
, . . 3.4 
. . . 3.3 


9 15 

12  7 

13  4 


Cream  3.5 

Dark  cream  4.4 

Light  tan  exterior ; bluestoned . . 4.5 


15  5 Light  tan ; bluestoned 

Fusion  test; — Cone  28. 


Rootlets  and  white 
quartz  grains 


White  sand  and  mica 
with  some  organic 
matter 
White  sand 


Per  cent 
..  4.9 
..  4.7 

. . 19.5 


Remarks 


Earthy  fracture 
Earthy  fracture 
Earthy  fracture,  slight 
veining  of  iron  stain 
Earthy  fracture 
Earthy  fracture 
Very  minute  glassy 
spots  on  and  in  the 
piece 


Summary 

The  strength  of  the  dry  clay  is  medium  high.  Its  bonding  strength  is  medium. 
The  amount  of  residues  on  the  screens  is  small.  The  drying  shrinkage  is  medium 
low  and  the  total  shrinkage  at  cone  9 is  medium.  It  is  a refractory  clay. 

Suggested  uses : Architectural  terra  cotta,  stoneware,  sanitary  ware,  face  brick, 
refractory  wares. 


Sample  No.  53 

(C.  T.  Hicks;  y$  mile  south  of  Drake) 

This  is  a hard  clay  of  a light  gray  color  mottled  with  brown  and  darker  gray 
color.  When  tempered  with  water  it  develops  a good  degree  of  plasticity  and  may 
be  made  to  flow  satisfactorily  through  a die. 

Water  of  plasticity  per  cent  17.2 

Shrinkage  water  per  cent  8.74 

Pore  water  per  cent  8.51 

Modulus  of  rupture *. lbs.  per  sq.  in.  120.2 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  103.1 

Screen  test: — 

Mesh  Residue  Character  of  residue 

Per  cent 

20 0.3  Quartz  grains,  rock 

grains  and  roots 


90 


ILLINOIS  FIRE  CLAYS 


40. 


60. 


80. 


120. 


200. 


.09  Quartz  grains,  rock 
grains  and  roots 

1.0  White  sand  with  dark- 

er particles 

0.4  White  sand  with  dark- 

er particles 

3.8  White  sand  with  dark- 

er particles 

4.6  White  sand  with  dark- 

er particles 


Drying  shrinkage 


Per  cent 
..  4.0 

..  3.8 


Linear;  dry  length 

Linear;  wet  length  

Volume  17.1 

Burning  test : — 


Cone 

Porosity 

Color 

Burning 

shrinkage 

Remarks 

02 

Per  cent 
26 

White  

Per  cent 
2.4 

Earthy  fracture 

3 

23 

Very  light  cream  

3.6 

Earthy  fracture  shows 

6 

22 

Very  light  cream 

4.4 

vanadium  (?)  stain 
Earthly  fracture.  Iron 

8 

19 

Very  light  cream 

4.6 

spots,  very  small 

9 

18.2 

Very  light  cream 

4.9 

12 

13.0 

Very  light  cream 

6.2 

13 

7.6 

Very  light  cream 

....  6.2 

Iron  spots,  very  small 

15 

7.0 

Bluestoned ; tan  exterior. . . 

7.5 

and  not  conspicuous 

Fusion  test : — Deforms  at  cone  30. 


Summary 

This  clay  has  a medium  low  strength  and  a medium  low  bonding  strength.  The 
amount  of  the  residues  left  upon  the  screens  is  moderate.  The  drying  shrinkage 
is  low.  Shrinkage  at  cone  8 is  medium.  Vitrification  proceeds  slowly  until  cone  13 
is  reached.  It  is  a refractory  clay. 

Suggested  uses : Face  brick,  architectural  terra  cotta,  sanitary  ware,  and  refrac- 
tories. 


Sample  No.  49 

(Clay  pit  east  of  White  Hall) 

This  is  a light  gray  colored  clay  with  brown  stains  which  is  moderately  hard. 
Good  plasticity  is  developed  upon  the  addition  of  water,  and  in  this  condition  it  flows 


readily  through  a die. 

Water  of  plasticity  per  cent  24.3 

Shrinkage  water  per  cent  11.2 

Pore  water  per  cent  13.1 

Modulus  of  rupture  lbs.  per  sq.  in.  369.2 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  189.5 

Slaking  test,  average min.  23 


GREENE  COUNTY 


91 


Screen  test : — 


Mesh  Residue  Character  of  residue 

Per  cent 

20 0.46  Colored  sand 

40 0.37  Colored  sand 

60 1.94  Colored  sand 

80 0.54  Colored  sand 

120 0.13  Colored  sand 

200 Trace  Colored  sand 


Drying  shrinkage : — 

Per  cent 

Linear ; wet  length  4.75 

Linear ; dry  length  4.98 

Volume  21.2 

Burning  test: — 

Burning 


Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

22.8 

Cream  

7.2 

3 

18.4 

Light  cream  

....  7.2 

Smooth  fracture ; very 

fine  iron  speck 

6 

16.5 

Cream  

....  7.2 

Smooth  fracture ; very 

fine  iron  speck 

8 

12.9 

Cream  

....  5.8 

9 

9.6 

Cream  

5.6 

Smooth  fracture,  very 

fine  iron  speck 

12 

0.5 

Gray  interior;  light  tan  exterior  7.0 

13 

1.01 

....  6.5 

15 

8.8 

Bluestoned  ; buff  exterior. . . 

6.0 

Very  small  iron  spots 

Fusion  test: — It  fused  at  cone  30. 


Summary 

The  clay  has  a medium  strength  and  medium  low  bonding  strength.  The  amount 
of  screen  residues  is  slight.  The  drying  shrinkage  is  medium  low  and  the  burning 
shrinkage  at  cone  9 is  medium.  The  clay  vitrifies  to  a porosity  of  less  than  one  per- 
cent between  cones  9 and  12.  Overburning  appears  at  about  cone  15. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  face  brick,  sanitary  ware, 
refractories. 


Sample  No.  52 

(Clay  pit  east  of  White  Hall) 

This  is  a hard  dark  gray  colored  clay  mottled  with  yellowish  brown.  When 
ground  and  tempered  with  water  it  develops  a good  plasticity  and  flows  readily 


through  a die. 

Water  of  plasticity  per  cent  23.0 

Shrinkage  water  per  cent  9.9 

Pore  water  per  cent  13.1 

Modulus  of  rupture  lbs.  per  sq.  in.  380.2 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  243.9 

Slaking  test,  average  min.  10 

Screen  test : — 


92 


ILLINOIS  FIRE  CLAYS 


Mesh  Residue  Character  of  residue 

Per  cent 

20 Trace  


35 0.12  Particles  of  shale,  coal 

and  sand 

48 0.10  Particles  of  shale,  coal 

and  sand 

65 0.15  Particles  of  shale,  coal 

and  sand 

100 2.0  Particles  of  shale,  coal 

and  sand  with  much 
mica 

150 3.8  Particles  of  shale,  coal 

and  sand  with  much 
mica 

200 8.1  Particles  of  shale,  coal 

and  sand  with  much 
mica 


Drying  shrinkage : — 

Per  cent 


Linear  ; dry  length  5.0 

Volume  18.5 


Burning 

test : — 

Cone 

Porosity 

Per  cent 

Color 

02 

21.6 

Light  tan 

1 

15.7 

Light  tan 

3 

10.6 

Tan 

5 

7.2 

Gray1  . . . 

8 

2.5 

Gray1  . . 

13 

1.6 

Gray  . . . . 

Fusion  test: — Fused  completely  at  cone  26. 


Total 
shrinkage 
Per  cent 
. 9.1 

Remarks 

. 10.4 

. 10.1  

. . 10.4 

Semi  vitreous  fracture 

. 11.3 

Vitreous  luster 

..  11.0 

Vitreous  luster,  con- 

choidal  fracture 


Summary 

The  clay  has  a medium  strength  and  a medium  bonding  strength.  The  screen 
residues  are  considerable.  The  drying  shrinkage  is  medium  low.  The  total  shrink- 
age at  cone  8 is  medium.  The  clay  is  well  vitrified  at  cone  8 and  is  not  overburned 
at  cone  13.  It  is  non-refractory. 

Suggested  uses : Stoneware,  sanitary  ware,  architectural  terra  cotta,  face  brick. 


Sample  No.  51 

(2*2  miles  northeast  of  White  Hall) 

This  is  a rather  hard  clay  of  a dark  brown  color  and  good  plasticity.  Its  con- 
duct when  squeezed  through  a die  is  fair. 

Water  of  plasticity  per  cent  24.0 

Shrinkage  water  per  cent  14.1 


iGrayish  color  may  be  due  to  reduction. 


GREENE  COUNTY 


93 


Pore  water  

Modulus  of  rupture  

With  50%  standard  sand — Modulus  of  rupture 

Slaking  test,  average 

Screen  test : — 

Mesh 

20 

60 

80 

120 

200 


Residue 
Per  cent 
. Trace 
. Trace 
. Trace 
. 0.18 
. 1.4 


per  cent  9.9 

.lbs.  per  sq.  in.  446.8 
.lbs.  per  sq.  in.  199 
min.  1 1 

Character  of  residue 


Colored  sand 
White  sand  and  mica 


Drying  shrinkage : — 

Per  cent 


Linear;  dry  length  6.4 

Linear ; wet  length  6 0 

Volume  27.8 


Burning  test : — 

Cone  Porosity 

Per  cent 

02  19. 

Color 

White  

Burning 

shrinkage 

Per  cent 

4.8 

Remarks 

3 

16.2 

Light  cream 

5.3 

Smooth,  fine  grain 
fracture 

6 

13.5 

Light  cream 

5.3 

Smooth  fracture,  near- 
ly vitreous 

sy2 

9.8 

Cream  

5.8 

Smooth  fracture,  near- 
ly vitreous 

9 

9.5 

Cream  

6.1 

Smooth  fracture,  near- 
ly vitreous 

12 

1.1 

Stoneware  gray,  uniform... 

7.6 

Smooth  fracture 

13 

0.5 

Stoneware  gray,  uniform... 

7.6 

Smooth  fracture 

Soluble  salts : — Pieces  burned  at  cone  02  give  a strong  yellow  surface  discoloration 
after  being  soaked  in  water. 

Fusion  test: — Deforms  at  cone  31. 


Summary 

The  strength  of  the  raw  clay  is  medium  high.  The  bonding  strength  is  medium 
low.  The  percentage  of  screen  residues  is  slight.  The  drying  shrinkage  is  medium. 
The  total  shrinkage  at  cone  9 is  medium.  Clay  is  well  vitrified  at  cone  12.  It  is  a 
refractory  clay. 

Suggested  uses : Refractories,  stoneware,  architectural  terra  cotta,  sanitary  ware, 
face  brick. 

Sample  No.  50 

(2^4  miles  northeast  of  White  Hall) 

This  clay  is  of  a dark  gray  color  with  some  portions  brown  and  other  reddish. 

It  is  quite  hard  but  a good  plasticity  is  developed  when  it  is  mixed  with  water  and 
properly  worked.  Its  conduct  when  flowing  through  a die  is  fair. 

Water  of  plasticity  per  cent  22.4 

Shrinkage  water  per  cent  10  6 

Pore  water  per  cent  11.8 


94 


ILLINOIS  FIRE  CLAYS 


Modulus  of  rupture  lbs.  per  sq.  in.  20 7 

With  50%  standard  sand — Modulus  of  rupture  lbs.  per  sq.  in.  275.5 

Slaking  test,  average  min.  11 

Screen  test : — 


Mesh 

Residue 

Character  of  residue 

Per  cent 

40... 

Quartz  particles 

60... 

Quartz  particles 

80... 

120... 

Mica  and  quartz  sand 

200... 

4.7 

Mica  and  quartz  sand 

Drying  sh 

rinkage : — 

Per  cent 

Linear;  dry  length  

5.9 

Volume  

21.8 

Burning  test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04 

28.6 

Light  tan,  pinkish  

0.13 

02 

25.1 

Cream,  pinkish  

1.5 

2 

20.6 

Light  tan  

3.1 

Very  fine  iron  spots 

5 

20.1 

Tan 

3.3 

9 

13.1 

Stoneware  gray  

4.6 

Smooth  fracture 

13 

10.8 

Stoneware  gray  

4.5 

Fusion  test: — It  fused  completely  at  cone  26. 


Summary 

The  strength  of  the  dry  clay  is  medium.  The  bonding  strength  is  medium. 

The  quantity  of  screen  residue  is  small.  The  shrinkage  at  cone  9 is  medium.  It  is  a 
non-refractory  clay. 

Suggested  uses : It  is  reported  as  being  used  for  sewer  pipe.  It  appears  adapted 

for  stoneware,  architectural  terra  cotta,  sanitary  ware,  and  face  brick. 

SCOTT  COUNTY 

The  clay  at  Alsey  underlies  5 feet  of  cherty  limestone,  above  which  there 
are  28  to  34  inches  of  coal.  Between  these  is  a 2-  to  3-foot  thickness  of 
dark,  shaly  clay.  Only  the  upper  part  of  the  lower  clay  is  dug,  as  the  lower 
beds  contain  much  pyrite.  Almost  the  entire  output  of  the  plant  had  come 
to  be  fire  brick  when  it  closed  in  February,  1918,  though  formerly  only 
building  brick  was  made. 

Production  ran  about  20,000  bricks  per  day  but  enlargement  of  the 
plant  insures  a possibility  of  double  that  quantity. 

The  United  States  Bureau  of  Standards  reports  above  the  signature  of 
A.  V.  Bleininger,  “In  the  fusion  test,  conducted  in  an  electric  furnace,  the 
softening  point  of  the  fire  brick  was  found  to  correspond  to  cone  31 or 
approximately  3083  degrees  F.  From  this  it  appears  that  the  fire  clay  may 
be  considered  of  No.  1 grade.” 


SCOTT  COUNTY 


95 


Sample  No.  71  was  taken  from  the  stock  pile  of  the  clay  used  for  fire 
brick  and  No.  70  from  the  clay  which  overlies  the  limestone.  Results  of 
tests  are  given  on  pages  96  and  97. 

The  Cheltenham  clay  is  exposed  in  the  bluff  of  Mauvais  Terre  Creek 
half  a mile  west  of  Exeter.  The  section  varies  in  short  distances,  and  the 
clay  is  stained  yellow  by  iron  along  seams  where  water  circulates.  Gypsum 
crystals  may  be  seen  on  the  weathered  surface.  This  clay  was  used  several 
years  ago  by  potteries  at  Exeter  and  Merritt. 

Section  along  Mauvais  Terre  Creek  half  a mile  west  of  Exeter 


Thickness 
Ft.  In. 

8.  Limestone;  weathers  to  rounded  boulders,  some  of  large  size. 

Hard;  fossiliferous  3 10 

7.  Clay,  yellow  and  impure  2 10 

6.  Clay,  dark  blue  3 10 

5.  Clay,  drab  yellow  irony  seams,  gypsum  crystals ; the  lower  4 feet 
sandy  and  not  included  in  sample ; probably  high  in  sulphur  and 

iron 12  6 

4.  Clay,  somewhat  colored  by  carbon  8 

3.  Coal  and  coaly  shale  1 0 to  6 

2.  Conglomerate,  sandy;  pebbles  up  to  the  size  of  a walnut 2 0 to  6 

1.  Limestone,  Mississippian ; cuts  out  both  conglomerate  and  coal 

nearby  


Sample  No.  65,  reported  on  pages  97  and  98,  includes  No.  6 and  part 
of  5 of  the  section. 

Section  at  small  coal  opening  on  Mauvais  Terre  Creek  about  4l/2  miles 


downstream  from  Exeter 

Thickness 
Ft.  In. 

8.  Clay  shale  4 

7.  ‘‘Slate”  or  carbonaceous  shale 2 

6.  Coal  (No.  2) 2 8 

5.  Covered  5 4 

4.  Limestone,  nodular;  same  as  number  8 of  previous  section 4 6 

3.  Clay,  impure,  stained  yellow 3 6 

2.  Limestone,  regular  bedded,  with  shale  partings 8 8 

1.  Clay  unmeasured 


At  outcrops  two  miles  northeast  of  Alsey  numerous  gypsum  crystals 
appear  on  the  surface  of  four  feet  of  clay  just  below  the  limestone.1 

If  conditions  here  are  similar  to  those  at  Alsey,  the  fire  clay  might  be 
expected  to  be  of  better  quality  east  of  the  outcrop  where  it  would  lie  at  a 
greater  depth.  The  record  of  the  city  well  at  Jacksonville,  Morgan  County, 
shows  five  feet  of  fire  clay  below  a coal  at  a depth  of  148  feet. 

Near  Franklin  six  feet  of  fire  clay  is  reported  at  a depth  of  347  feet. 


lOp.  cit.,  p.  68. 


96 


ILLINOIS  FIRE  CLAYS 


RESULTS  OF  TESTS 
SCOTT  COUNTY 


Sample  No.  71 
(Abandoned  plant  at  Alsey) 


The  sample  is  a hard  material  of  a dark  gray  color.  When  tempered  with 
water  it  becomes  very  plastic.  Its  conduct  in  flowing  through  a die  is  fair. 


Water  of  plasticity per  cent  21.8 

Shrinkage  water per  cent  10.9 

Pore  water  per  cent  10.9 

Modulus  of  rupture  lbs.  per  sq.  in.  328 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  144 

Slaking  test,  average min.  10 

Screen  test : — 

Mesh  Residue 

Per  cent 

20 0.6 

40 0.13 

60 0.11 

80 0.14 

120 Trace 

200 Trace 


Drying  shrinkage : — 


Linear ; dry  length 
Linear ; wet  length 
Volume  


Burning  test : — 

Total 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

02  16  Cream  7.1 

3 15  Light  cream 5.3 

5 14  Light  cream  6.0 

6 12.7  Light  cream 6.0 

8 11.2  Light  cream 

9 10  Cream  6.6 


12  — Bluestoned  ; light  buff  outside. . . 9 


13  1.0  Bluestoned  

15  3.4  Buff  exterior ; bluestoned  (black)  8.9 

Fusion  test: — It  deforms  between  cones  30  and  31. 


Per  cent 
..  5.9 
..  5.6 
..  21.4 


Remarks 

Vanadium  stain  (?) 
Vanadium  stain  (?) 


Contains  fine  black 
specks 


Summary 

The  clay  has  a medium  strength  and  a medium  low  bonding  strength.  The 
amount  of  screen  residues  is  slight.  Drying  shrinkage  is  medium  and  total  shrinkage 
at  cone  9 is  medium  high.  It  is  practically  non-porous  at  cone  13  and  apparently 
shows  slight  overburning  at  cone  15.  It  is  a refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  face  brick,  sanitary  ware, 
refractories. 


SCOTT  COUNTY 


97 


Sample  No.  70 
(Abandoned  plant  at  Alsey) 

This  is  a grayish  colored  clay  of  medium  hardness.  It  is  very  plastic  when 


tempered  with  water. 

Water  of  plasticity per  cent  41.8 

Shrinkage  water per  cent  31.4 

Pore  water  per  cent  10.4 

Modulus  of  rupture  lbs.  per  sq.  in.  609 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  302.8 

Slaking  test,  average min.  7 

Drying  shrinkage,  linear per  cent  12.5 

Screen  test : — 


Mesh 

Residue 

Character  of 

residue 

Per  cent 

10... 

Hard 

lumps  of  black  shale 

14... 

Trace 

Hard 

lumps  of  black  shale 

20... 

0.85  ] 

| 

35... 

6.8  | 

48... 

7.4 

65... 

7.4 

l Hard 

lumps  of  black  shale 

with  particles-  of 

100... 

5.1 

150... 

8.1 

200... 

8.5 

Burning  te  t — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04 

20 

Yellow  cream  

2.9 

Hackly  fracture 

02 

18 

Dark  cream  . 

4.7 

Hackly  fracture 

2 

7.5 

Buff  cream  . . 

6.2 

Hackly  fracture 

5 

3.5 

Buff  cream  . . 

5.9 

Hackly  fracture 

9 

2.5 

Gray ; bluestoned  . . 

6.8 

Hackly  fracture 

13 

10 

Light  tan  ; bluestoned. . . 

5.6 

Black  core 

14 

9 

21.5 

Bloated 

Fusion  test: — It  fuses  at  cone  26.  Vesicular  structure. 


Summary 

The  clay  has  a medium  high  strength  and  medium  bonding  strength.  The  dry- 
ing shrinkage  is  high.  The  total  shrinkage  at  cone  9 is  high.  It  is  fairly  well  vitrified 
at  cone  2 and  is  overburned  at  cone  13.  The  oxidation  rate  is  slow. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  face  brick. 

Sample  No.  65 

(Bluff  of  Mauvais  Terre  Creek  mile  west  of  Exeter) 

This  is  a brownish  colored  shaly  clay.  It  becomes  very  plastic  when  tempered 
with  water.  It  flows  satisfactorily  through  a die. 


98 


ILLINOIS  FIRE  CLAYS 


Water  of  plasticity  . . 

Shrinkage  water 

Pore  water  

Modulus  of  rupture  . , 
Slaking  test,  average 
Screen  test : — 

Mesh 


per  cent  22.0 

per  cent  9.9 

per  cent  12.0 

, lbs.  per  sq.  in.  240.8 
min.  6 


20 

40 

60 

80 

120 

200 

Drying  shrinkage : — 

Linear ; dry  length 
Linear ; wet  length 

Volume  

Burning  test: — 


Residue 
Per  cent 
. 0.22  "] 
. 0.40 

. 0.77 
. 0.64 

. 2.9 

. 2.3 


Character  of 
residue 


Colored  sand 


Per  cent 
. . 4.9 
. . 4.7 

..  18.7 


Cone 

Porosity 

Color 

Burning 

shrinkage 

Remarks 

02 

Per  cent 
24 

Pinkish  cream 

Per  cent 
3.1 

1 

24 

Pinkish  cream 

3.1 

3 

22 

Medium  cream  

3.8 

Fine  iron  specks,  earthy 

5 

21 

Medium  cream  

4.0 

fracture 

6 

21 

Medium  cream  

4.2 

Fine  iron  specks  ; earthy 

9 

17 

Light  tan  

4.3 

fracture 

Numerous  fine  iron 

12 

9 

Darker  tan 

6.2 

specks 

Numerous  fine  iron 

13 

3.5 

Rlnestoned  

6.6 

specks 

15 

3.3 

Buff  exterior  ; bluestoned  (black)  6.7 

Iron  spots 

Fusion  test: — It  deforms  between  cones  26  and  27. 


Summary 

This  clay  has  a medium  strength  and  a medium  low  drying  shrinkage.  The 
total  shrinkage  at  cone  9 is  medium.  It  is  well  vitrified  at  cone  13  and  not  over- 
burned at  cone  15.  It  is  a non-refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  for  which 
uses  it  should  be  washed,  face  brick. 


PIKE  COUNTY 

Clay  outcrops  in  the  west  bluff  of  Illinois  River  at  Bedford.  The  rela- 
tion to  the  Mississippian  limestone  at  the  north  suggests  faulting.  Twenty- 
seven  feet  of  clay  are  exposed  above  and  16  or  more  feet  below.  This  thick- 
ness makes  the  deposit  of  special  interest. 


PIKE  COUNTY 


99 


Section  of  the  river  bluff  at  Bedford 

Thickness 
Ft.  In. 


7.  Loess  and  loose  limestone  blocks  to  top  of  mound 50 

6.  Covered,  cherty  fragments  over  slope 10 

5.  Clay,  bluish  gray;  partly  covered  yellow  iron  stains  in  lower  part 

(Sample  No.  67)  27 

4.  Covered  interval  11  6 

3.  Partly  covered,  probably  clay 9 

2.  Clay,  blue  (Sample  No.  69) 16  6 

1.  Partly  covered  to  water  level  in  Illinois  River;  loose  blocks  indi- 
cate Mississippian  limestone  in  the  lower  part  of  this  interval. . . 20 


Clay  has  been  dug  in  small  amounts  about  2 miles  north  of  Pittsfield 
and  used  as  a blend  for  surface  clay  in  making  building  brick  and  drain 
tile  and  possibly  also  for  pottery.  This  deposit  (sample  No.  66,  p.  101)  is 
reported  to  vary  from  6 to  13  feet  in  thickness.  It  is  of  a bluish  white  color 
where  exposed  and  has  an  overburden  of  drift  and  loess  up  to  20  feet  in 
thickness.  Boring  has  shown  that  the  clay  extends  back  under  the  bluff  over 
an  area  of  several  acres  and  the  topography  suggests  that  extensive  areas  are 
underlain  by  clay  both  to  the  south  and  east. 


RESULTS  OF  TESTS — PIKE  COUNTY 


Sample  No.  67 

(West  bluff  of  Illinois  River  at  Bedford) 

This  is  a gray  colored,  soft  clay  which  develops  a good  plasticity. 


Water  of  plasticity per  cent  26.5 

Shrinkage  water  per  cent  12.5 

Pore  water  per  cent  14.0 

Modulus  of  rupture lbs.  per  sq.  in.  303.8 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  248.7 

Slaking  test,  average min.  15 


Screen  test : — 

Mesh 

40 

60 

80 

120 

200 

Drying  shrinkage : — 

Linear;  dry  length 
Linear;  wet  length 
Volume  


Residue 

Character  of 

Per  cent 

residue 

. . . 0.12 

Quartz  sand,  and  pyrite 

. . . 0.4 

Quartz  sand,  and  pyrite 

. . . Trace 

. . . 0.3 

Sand  and  some  pyrite 

. . . 0.3 

Sand  and  some  pyrite 

Per  cent 

6.4 

6.0 

23.9 


100 


ILLINOIS  FIRE  CLAYS 


Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

04  25.4  Terra  cotta 2.1 

02  16.6  Light  red  brown  4.8 

2 6.7  Brown  7.4 

5 2 Brown-red  5.6 


9 2.7  Brown-red  

Fusion  test : — It  fused  to  glass  at  cone  25. 


Remarks 


Hackly  fracture 
Vitreous,  appears  to  be 
overburned 
Overburned  badly 


Summary 

The  clay  has  a medium  strength  and  a medium  bonding  strength.  The  drying 
shrinkage  is  medium.  The  total  shrinkage  at  cone  5 is  medium  low.  At  cone  9 the 
sample  is  overburned.  It  is  a non-refractory  clay. 

Suggested  uses:  Face  brick,  sewer  pipe,  hollow  block,  paving  brick  (?). 


Sample  No.  69 


(West  bluff  of  Illinois  River  at  Bedford) 

This  is  a clay  of  a uniform  gray  color,  containing  some  shaly  particles.  It  is 
very  plastic  when  tempered  with  water.  The  flowing  conduct  of  the  clay  when 


forced  through  a die  is  satisfactory. 

Water  of  plasticity per  cent  24.7 

Shrinkage  water per  cent  13.5 

Pore  water  per  cent  11.2 

Modulus  of  rupture  lbs.  per  sq.  in.  498.3 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  242.0 

Slaking  test,  average  min.  14 

Screen  test : — 

Mesh  Residue 

Per  cent 

20 None 

40 Trace 

60 0.3 

80 Trace 

120 0.2 

200 0.2 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  6.6 

Volume  26 


Burning 

test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04 

26.5 

Terra  cotta  

4.8 

Hackly  fracture 

02 

14.4 

Terra  cotta 

4.9 

Hackly  fracture 

2 

1.8 

Reddish  brown 

7.6 

Hackly  fracture 

5 

24 

Reddish  brown  

Overburned 

9 

19.9 

Red-brown 

Swelled 

PIKE  COUNTY 


101 


Fusion  test : — Bloated  and  fell  over  before  cone  8 in  a Fletcher  furnace. 

Summary 

This  clay  has  a medium  high  strength,  a medium  bonding  strength,  and  a me- 
dium drying  shrinkage.  The  total  shrinkage  at  cone  2 is  medium ; vitrification  pro- 
ceeds rapidly  and  is  practically  complete  at  cone  2.  It  is  overburned  at  cone  5. 
Suggested  uses : Common  brick,  drain  tile. 


Sample  No.  66 


(2  miles  north  of  Pittsfield) 

This  is  a soft  clay,  colored  yellow  to  dark  brown.  A fair  degree  of  plasticity 
may  be  developed. 

Water  of  plasticity  

Shrinkage  water  

Pore  water  

Modulus  of  rupture  

Slaking  test,  average  

Screen  test : — 

Mesh  Residue 

Per  cent 

20 0.08 


per  cent  27 

per  cent  13.5 

per  cent  13.5 

. .lbs.  per  sq.  in.  414.5 
min.  11 

Character  of  residue 


40. 

60. 

80. 

120. 

200. 


Trace 

Trace 

Trace 

0.79 

1.32 


Rock  particles  and  or- 
ganic matter 


White  sand  and  root- 
lets 

White  sand  and  root- 
lets 


Drying  shrinkage  : — 

Linear ; dry  length 

Volume  

Burning  test 


Per  cent 
..  8.2 
..  24.5 


Cone 

02 

2 

3 


Porosity 
Per  cent 

17 

14 

12 


Color 


Burning 
shrinkage 

Per  cent 

Cream  4.9 

Cream  5.1 

Medium  cream  5.8 


Medium  cream  6.2 


Remarks 


1.2 


Stoneware  gray  6.3 


Smooth  fracture;  fine 
iron  specks  (?); 
none  on  another  trial 
piece 

Smooth  fracture;  fine 
iron  specks  (?); 
none  on  another  trial 
piece 

Somewhat  conchoidal 
fracture 

Vitreous 


102 


ILLINOIS  FIRE  CLAYS 


12 

1.0 

Gray  white  

5.0 

Fine  veining  of  iron 
stain ; good  color 

13 

1.6 

Gray  white 

4.5 

15 

3.8 

Gray  white  

4.5 

Fine  iron  spots 

Fusion  test: — It  deformed  at  cone  29. 


Summary 

The  sample  is  a clay  of  medium  high  strength  which  has  a medium  drying 
shrinkage.  The  total  shrinkage  at  cone  9 is  medium  high.  Vitrification  is  practi- 
cally complete  between  cones  6 and  9.  There  are  some  indications  of  overburning 
at  cone  15.  It  is  a refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  a plastic 
bond  for  refractories. 

ADAMS  COUNTY 

Toward  the  west  the  basal  clays  of  the  Pennsylvanian  contain  more 
gypsum,  and  are  generally  streaked  by  yellowish  and  buff  iron  markings. 
In  a road  cut  2^4  miles  north  and  one  mile  west  of  Camp  Point,  8}4  feet 
of  distinctly  bedded  clay  are  exposed.  The  upper  2*4  feet  are  tough,  ash 
colored  clay,  containing  much  gypsum  sand  and  small  gypsum  crystals,  and 
colored  by  streakings  of  iron.  An  overburden  of  from  5 to  15  feet  of  gravel 
and  clayey  till  with  locally  thin  sandstone  layers  immediately  above  the  clay, 
forms  the  covering. 


BROWN  COUNTY 

On  Crooked  Creek  in  the  vicinity  of  Ripley,  clay  has  been  dug  for  stone- 
ware. The  old  pits  one  mile  south  of  Ripley  are  almost  obliterated  by  sur- 
face wash  and  caving.  Since  the  clay  directly  underlies  the  drift  it  does 
not  promise  to  be  of  refractory  value. 


SCHUYLER  COUNTY 

At  a small  mill  and  kilns  at  Frederick,  drain  tile  is  manufactured  from 
a mixture  of  surface  clay  and  bedded  Coal  Measures  clay. 

Section  of  the  clay  pit  at  Frederick 

Thickness 
Ft.  In. 


5.  Loess 9 

4.  “Potter’s  clay”  8 

3.  Coal  (“peacock  vein”)  3 3 

2.  Clay,  drab  and  sandy;  plant  remains  and  yellow  iron  stains 10 

1.  Shale,  blue  


MC  DONOUGH  COUNTY 

“The  line  of  outcrop  of  the  clay  in  McDonough  County  extends  along 
the  bluffs  and  ravines  of  the  east  fork  of  Crooked  Creek  from  Bardolph  to 
the  county  line  on  the  north  side  and  Tennessee  on  the  south  side,  whence 
it  extends  southeast  toward  Schuyler  County.”1  Clay  is  being  dug  about 


!Op.  cit.,  p.  70. 


MC  DONOUGH  COUNTY 


103 


Colchester  and  from  a pit  about  3 miles  northeast  of  Macomb. 

At  the  open  pit  of  the  Macomb  Sewer  Pipe  Works  about  3 miles  north- 
east of  Macomb  the  clay  is  stripped,  loaded  by  steam  shovel,  and  hauled 
over  a standard  gauge  track  to  the  plant  at  Macomb.  Samples  No.  73a, 
No.  73b,  and  No.  73c  are  respectively  from  the  top,  middle  and  bottom  of 
a boring  on  the  Company’s  property.  Results  of  tests  are  given  on  pages 
105  and  106.  A section  of  the  face  of  the  pit  is  as  follows : 


6. 

5. 

4. 

3. 

2. 

1. 


Section  of  the  face  of  the  pit  of  the  Macomb  Sewer  Pipe  Works, 
3 miles  northeast  of  Macomb 


Thickness 


Feet 

Loess,  drift,  and  soil  20  to  25 

Sandstone,  hard,  and  chert  6 

Coal  traces  

Clay,  used  for  sewer  pipe  10 

Pebbles  and  iron  concretions  in  layer 

Shale,  dark  blue  10-}- 


The  Colchester  Brick  and  Tile  Company  uses  the  clay  from  this  horizon 
at  its  plant  near  Colchester  in  the  manufacture  of  refractory  brick,  tile,  and 
silo  blocks.  The  clay  is  dug  from  an  open  pit  in  the  side  of  a hollow  (fig. 
54)  and  hauled  by  wagon  to  the  mill. 


Section  of  Colchester  Brick  and  Tile  Company’s  pit,  half  a mile 
north  of  Colchester 

Thickness 
Ft.  In. 


7.  Shale,  sandy  20 

6.  Shale,  dark,  and  coal  2 

5.  Fireclay,  poor  grade  3 

4.  Shale,  dark  6 

3.  Fireclay,  stained  yellow  by  iron  (Sample  No.  75a) 6 

2.  Shale 7 

1.  Fireclay  (Sample  No.  75b)  10 


Sample  No.  75a  is  from  No.  3,  and  sample  No.  75b  from  No.  1 of  the 
above  section.  Results  of  tests  are  given  on  pages  106  to  108. 

Most  of  the  clay  obtained  about  Colchester  is  taken  from  mines  west 
of  town.  The  clay  taken  from  the  shaft  of  the  Gates  Fireclay  Company  is 
used  for  making  flue  linings  among  other  clay  products. 


Log  of  shaft  at  the  Gates  Fireclay  Company’s  mine,  near  Colchester 


Thickness 

Depth 

Description  of  strata 

Feet 

Feet 

Soil  and  glacial  clay 

24 

24 

“Soapstone,”  compact  shale  

26 

50 

Coal  (No.  2) 

2'A 

52^ 

Fireclay,  used  in  the  manufacture  of  flue  linings,  etc., 

“upper  vein” 

(Sample  No.  88,  see  pages  108-109) 

55d 

58 

104 


ILLINOIS  FIRE  CLAYS 


Log  of  Gates  Fireclay  Company’s  mine  shaft — Continued 


Limestone,  scattered  boulders  

"Hard  rock,”  probably  sandstone  6 64 

Clay,  "middle  vein”  8 72 

Sandstone 5 77 

Shale  8 85 


The  firm  of  Baird  Brothers  is  operating  a mine  one  mile  northwest  of 
Colchester  in  a 7-  to  8-foot  bed  of  clay  that  lies  below  the  “middle  vein” 
of  the  Gates  shaft.  On  the  Valentine  farm  three  drift  tunnels  have  been 
opened  into  a 7-  to  8-foot  bed  of  clay,  and  about  150  tons  are  taken  out 


Fig.  54.  View  of  the  Colchester  Brick  and  Tile  Company’s  pit  half  a mile  north  of  Col- 
chester showing  No.  2 coal  near  the  top  and  stoneware  clay  at  the  base. 

per  day.  One  hundred  and  twenty  acres  of  the  adjoining  Forncuff  farm  are 
underlain  by  the  lower  and  upper  clay.  The  middle  clay  contains  so  many 
boulders  that  it  cannot  be  worked  profitably.  The  clay  is  hauled  by  steam 
locomotive  over  a tram  to  tipple  at  the  Chicago,  Burlington  and  Quincy 
Railroad  at  Colchester. 

Sample  No.  74  (p.  109)  is  from  south  mine,  and  sample  No.  78  (p. 
110)  from  the  north  mine  on  the  Valentine  farm.  Sample  No.  75  (p.  Ill) 
was  taken  from  a carload  of  clay  as  it  came  from  the  Meyers  mine,  west 
of  the  Baird  mines. 

Two  other  mines  were  being  operated  in  June,  1918;  one  3 miles  west 
of  town  in  the  same  bed  as  are  the  above  mines,  another  2 y2  miles  west 
where  the  No.  2 coal  and  the  underlying  clay  are  both  recovered. 


MC  DONOUGH  COUNTY 


105 


RESULTS  OF  TESTS 


MCDONOUGH  COUNTY 


Sample  No.  73-a 

(Macomb  Sewer  Pipe  Works ; 3 miles  northeast  of  Macomb) 

The  sample  is  a gray  shaly  material,  containing  many  mica  flakes.  It  becomes 
very  plastic  when  worked  with  water. 


Water  of  plasticity  per  cent  28.3 

Shrinkage  water  per  cent  12.9 

Pore  water  per  cent  15.4 

Modulus  of  rupture  lbs.  per  sq.  in.  352.2 

Slaking  test,  average min.  13 

Drying  shrinkage : — 

Per  cent 

Linear  ; dry  length 6.5 

Volume  22.9 

Eurning  test  :— 

Total 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

1 16  Cream  10.6 

5 10  Cream  12.4 

9 4.8  Light  gray  13.1 

15  2.1  Light  gray 10.0 


Fusion  test: — Cone  slightly  deformed  at  cone  26.  Vesicular  at  cone  27. 

Summary 

The  clay  has  a medium  strength.  The  drying  shrinkage  is  medium  and  the 
total  shrinkage  at  cone  9 is  medium  high.  It  has  a low  porosity  at  cone  9 and  has 
only  a slight  porosity  at  cone  15.  It  is  non-refractory. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  face  brick. 


Sample  No.  73-b 

(Macomb  Sewer  Pipe  Works  ; 3 miles  northeast  of  Macomb) 

This  is  a rather  hard  clay,  varying  in  color  from  a light  to  a dark  gray.  When 
tempered  with  water  it  becomes  very  plastic  and  flows  satisfactorily  through  a die. 

Water  of  plasticity  per  cent  24.9 

Shrinkage  water  per  cent  11.9 

Pore  water  per  cent  13.0 

Modulus  of  rupture lbs.  per  sq.  in.  356.5 

Slaking  test,  average  min.  9 

Drying  shrinkage : — 


Pet  cent 


Linear  6.2 

Volume  21.8 


Burning  test: — 


Cone 

Porosity 

Color 

Total 

shrinkage 

Remarks 

1 

Per  cent 

10.9 

Light  brown  

Per  cent 
13.7 

Poorly  oxidized 

5 

5.1 

Brown  

14.0 

9 

0.4 

Dark  brown 

12.5 

15 

0.0 

Dark  gray  

11.2 

Overburned,  beginning 

to  bloat 


106 


ILLINOIS  FIRE  CLAYS 


Fusion  test: — At  cone  26  the  cone  was  deformed  half  way  and  showed  many  bubbles 
on  the  surface. 


Summary 

The  strength  is  medium.  The  drying  shrinkage  is  medium.  Burning  shrinkage 
at  cone  9 is  medium.  It  burns  to  a dense  body  at  cone  5 and  is  practically  non- 
porous  at  cone  9.  At  cone  15,  signs  of  overburning  appear.  It  is  non-refractory. 
Suggested  uses : Sewer  pipe,  face  brick,  possibly  paving  brick. 


Sample  No.  73-c 

(Macomb  Sewer  Pipe  Works ; 3 miles  northeast  of  Macomb) 


This  is  a hard 

dark  gray-colored 

clay  which  develops 

a very  good  plasticity. 

Water  of  plasticity  . 

Shrinkage  water  . . . 

Pore  water  

Modulus  of  rupture 

Slaking  test,  average  

Drying  shrinkage : — 

Per  cent 

Linear  

7.0 

Volume  

16.8 

Burning  test : — 

Total 

Cone  Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

1 11.2 

Cream  

12.5 

5 4.0 

Cream  

14.4 

Conchoidal  vitreous 

fracture 

9 0.2 

Gray  

14.4 

Conchoidal  vitreous 

fracture 

15  0.8 

Gray  

11.2 

Conchoidal  vitreous 

fracture 

Fusion  test: — Y deformed  at  cone  27.  Vesicular. 


Summary 

The  clay  has  a medium  strength.  The  drying  shrinkage  is  medium  and  the 
total  shrinkage  at  cone  9 is  medium  high.  It  attains  a low  porosity  at  cone  5 and  is 
completely  vitrified  between  that  and  cone  9.  It  is  a refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  face  brick,  sanitary  ware, 
and  some  types  of  refractories. 


Sample  No.  75-a 

(Colchester  Brick  and  Tile  Company’s  pit;  mile  north  of  Colchester) 

This  is  a clay  which  is  not  of  a uniform  color,  varying  from  gray  to  yellowish 
brown.  The  gray  portions  are  harder  than  the  yellow.  Tempered  with  water,  it 
develops  a medium  plasticity.  When  squeezed  through  a die,  it  flows  rather  badly. 


Water  of  plasticity per  cent  25 

Shrinkage  water  per  cent  7.6 

Pore  water  per  cent  17.3 

Modulus  of  rupture lbs.  per  sq.  in.  269.6 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  192 

Slaking  test,  average min.  4 


MC  DONOUGH  COUNTY 


107 


Screen  test : — 
Mesh 

40 

60 

80 

120 


Residue  Character  of 

Per  cent  residue 

0.2  White  and  colored  sand 

1.4  White  and  colored  sand 

0.3  White  and  colored  sand 

3.3  White  and  colored  sand 

and  mica 

200 3.7  White  and  colored  sand 

and  mica 

Drying  shrinkage : — 

Pet  cent 

Linear ; dry  length  4.7 

Linear ; wet  length  4.5 

Volume  11.2 

Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage  Remarks 

Per  cent 

Light  red  1.0  

Light  red  1.7  

Dark  tan  4.4 

Brown 8.2 


04 

02 

5 

9 

13 


Porosity 
Per  cent 
33 
30 
23.3 
13.5 
16.9 


Hackly  fracture 
Hackly  fracture 
Overburned 


Fusion  test- — It  fused  completely  at  cone  26. 


Summary 

The  clay  has  a medium  strength,  a medium  low  bonding  strength,  a medium 
low  drying  shrinkage,  and  a medium  high  total  shrinkage  at  cone  9.  Minimum 
porosity — 13.5% — is  attained  at  cone  9 and  overburning  appears  at  cone  13.  It  is  a 
non-refractory  clay. 

Suggested  uses  : Brick,  tile. 


Sample  No.  75-b 

(Colchester  Brick  and  Tile  Company’s  pit;  y2  mile  north  of  Colchester) 


This  is  a hard  gray-colored  clay,  having  an  irregular  fracture.  When  tempered 
with  water,  it  develops  a good  plasticity  and  flows  well  through  a die. 


Water  of  plasticity  per  cent  20.0 

Shrinkage  water  per  cent  8.6 

Pore  water  per  cent  11.4 

Modulus  of  rupture  lbs.  per  sq.  in.  263 

With  50%  standard  sand — Modulus  of  rupture  lbs.  per  sq.  in.  199.6 

Slaking  test,  average  min.  8 

Screen  test : — 


Mesh  Residue  Character  of  residue 

Per  cent 

20 0.3  Rock  particles 

40 0.9  Rock  particles  and  quartz  sand 

60 2.1  Rock  particles  and  quartz  sand 

80 0.3  Rock  particles  and  quartz  sand 

120 1.4  Quartz  sand  and  mica 

200 2.2  Quartz  sand  and  mica 


Drying  shrinkage : — 


Linear  

Volume  

Burning  test : — 

Cone  Porosity 
Per  cent 

04  30 

Color 

White  

Burning 
shrinkage 
Per  cent 

0.1 

Per  cent 

4.8 

Remarks 

02 

28 

Cream  

0.5 

2 

25.5 

Cream  

1.7 

Hackly  fracture 

5 

25.0 

Cream  

2.0 

Hackly  fracture 

9 

17.4 

Gray  white  

3.0 

A very  few  fine  iron 
spots 

13 

6.3 

Stoneware  gray  

5.2 

Many  slagged  iron 
spots 

14 

68 

Ruff  

2.7 

Fusion  test 

: — Completely  deformed  at  cone  26. 

Not  fused  as 

much  as  75-a. 

Summary 

The  strength  of  the  clay  is  medium.  Its  bonding  strength  is  medium.  The 
drying  shrinkage  is  medium  low  and  total  shrinkage  at  cone  9 is  medium.  The 
porosity  is  low  at  cone  14  but  vitrification  is  incomplete.  It  is  a non-refractory  clay. 
Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  face  brick. 


Sample  No.  88 

(Gates  Fireclay  Company’s  mine,  near  Colchester) 

This  is  a dark  colored,  very  hard  clay,  which  becomes  very  plastic  when  tem- 


pered with  water. 

Water  of  plasticity per  cent  27.7 

Shrinkage  water  per  cent  11.7 

Pore  water per  cent  15.9 

Modulus  of  rupture lbs.  per  sq.  in.  496 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  243 

Slaking  test,  average  min.  14 


Screen  test : — 
Mesh 

20 

40 

60 

80 

120 

200 


Residue  Character  of 

Per  cent  residue 

. None  

. Traces  

0.29  Dark  red  grains 

. 0.2  

. 2.8  

. 1.0  


Drying  shrinkage : — 

Per  cent 


Linear ; dry  length  7.2 

Linear ; wet  length  6.7 

Volume  28 


MC  DONOUGH  COUNTY 


109 


Burning  test : — 


Burning 


Cone 

Porosity 
Per  cent 

Color 

shrinkage 

Per  cent 

Remarks 

01 

0.8 

Tan  

....  7.7 

Vitreous  fracture 

2 

0.6 

Darker  tan 

. . . . 7.6 

Vitreous  fracture 

3 

0.5 

Grayish  tan  

....  7.3 

Vitreous  fracture 

4 

0.7 

Grayish  tan  

. . . . 6.9 

Vitreous  fracture 

6 

0.8 

Dark  gray  

...  6.9 

Vitreous  fracture 

9 

2.6 

Stoneware  gray  

. . . . 7.3 

Numerous  fine  iron 
spots ; vitreous  frac- 
ture 

12 

4.4 

Bluestoned,  surface  flashed. 

. . . . 4.0 

Numerous  fine  iron 
spots ; vitreous  frac- 
ture 

13 

2.2 

Buff  exterior 

. . . . 2.6 

Many  fine  iron  spots ; 
blue  core 

Fusion  test: — Partly 

deformed  at  cone  27. 

Summary 

The  strength  of  the  unburned  clay  is  medium  and  its  bonding  strength  is  medium. 
The  amount  of  residue  on  the  sieve  is  low.  The  drying  shrinkage  is  medium  and 
the  total  shrinkage  when  burned  at  cone  9 is  medium  high.  It  is  practically  non- 
porous  at  cone  01  which  is  an  unusually  low  temperature  and  shows  distinct  over- 
burning at  cone  13.  The  sample  burned  at  that  temperature  appears  to  be  reduced. 
It  is  a refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  refractories  (particularly 
when  good  bonding  properties  are  required),  sanitary  ware,  face  brick. 


Sample  No.  74 

(Valentine  farm,  south  mine;  near  Colchester) 

This  is  a dark  gray  colored  clay  which  becomes  very  plastic  upon  the  addition 


of  water. 

Water  of  plasticity  per  cent  22.0 

Shrinkage  water  per  cent  8.0 

Pore  water  per  cent  14.0 

Modulus  of  rupture lbs.  per  sq.  in.  221.8 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  214.9 

Screen  test : — 

The  sample  would  not  slake  satisfactorily  for  this  test. 

Slaking  test,  average min.  8 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  4.8 

Linear ; wet  length  4.6 

Volume  15.0 

Burning  test : — 

Burning 

Cone  Porosity  Color  shrinkage  Remarks 

Per  cent  Per  cent 

1 21  Cream  2.2  


2 20  Cream  2.3 


110 


ILLINOIS  FIRE  CLAYS 


3 

20 

Cream  

..  2.3 

Fine  iron  speck 

6 

17.9 

Slightly  darker  

..  3.2 

Fine  iron  speck 

9 

13.4 

Cream  

. . 3.5 

Fine  iron  speck 

12 

9.0 

Cream  

. . 4.0 

Numerous  quartz 
grains  ; fine  iron  spots 

13 

4.1 

Buff  

. . 4.4 

Iron  spots,  small ; 
slagged 

15 

3.9 

Bluestoned  ; buff  exterior  . . . 

..  4.3 

Slagged  iron  spots 

Fusion  test: — Cone  half  way  down  at  cone  26. 


Summary 

The  clay  has  a medium  strength  and  medium  bonding  strength.  Drying  shrink- 
age is  medium  low  and  total  shrinkage  at  cone  9 is  medium.  It  is  non-refractory. 

Weathering  or  aging  will  improve  its  working  properties. 

Suggested  uses : Face  brick,  stoneware,  and  terra  cotta.  But  its  slow  slaking 
character  as  noted  under  the  screen  test  may  limit  its  usefulness  for  the  latter  pur- 
poses. 


Sample  No.  78 

(Valentine  farm,  north  mine ; near  Colchester) 

This  is  a hard  dark  gray  colored  clay  which  may  be  brought  to  a very  plastic 
condition.  Its  conduct  when  flowing  through  a die  is  very  good. 

Water  of  plasticity per  cent  19. 

Shrinkage  water per  cent  9.4 

Pore  water  per  cent  9.6 

Modulus  of  rupture lbs.  per  sq.  in.  325.8 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  209.4 

Slaking  test,  average  min.  7 

Screen  test : — 

Character  of  residue 


Mesh 

Residue 

Per  cent 

20 

0.8 

Hard 

40 

0.7 

Hard 

60 

0.7 

Hard 

80 

0.22 

Hard 

120 

0.75 

Hard 

200 

0.7 

Hard 

Per  cent 
. . 4.1 


Drying  shrinkage : — 

Linear ; dry  length 

Linear;  wet  length  4.0 

Volume 16.9 

Burning  test 


Cone 

Porosity 

Color 

Burning 

shrinkage 

Remarks 

01 

Per  cent 
23 

Cream  white  

Per  cent 
2.8 

Granular 

fracture 

1 

23 

Cream  white  

2.6 

Granular 

fracture 

3 

20 

Cream  white  

3.3 

Granular 

fracture 

6 

18 

Cream  white  

4.0 

Granular 

fracture 

8 

18 

Cream  



Granular 

fracture 

9 

14.9 

MC 

Cream  

DONOUGH  COUNTY 

4.0 

111 

12 

9.0 

Dark  cream  or 

light  tan 

5.2 

Earthy  fracture.  Nu- 
merous fine  iron 
specks.  Also  quartz 
grains. 

15 

6.5 

Buff  exterior; 

bluestoned 

7.2 

Numerous  iron  spots. 
Slagged. 

Fusion  test No  deformation  at  cone  25.  It  deforms  at  cone  29. 

Summary 

The  strength  of  the  unburned  clay  is  medium.  Its  bonding  strength  is  medium. 
The  drying  shrinkage  is  medium  low.  The  total  shrinkage  at  cone  9 is  medium.  A 
low  porosity  is  not  reached  until  cone  15.  It  is  a refractory  clay. 

Suggested  uses : Architectural  terra  cotta,  stoneware,  sanitary  ware,  refractories, 
and  face  brick. 


Sample  No.  75 

(Meyers  mine;  near  Colchester) 

This  is  a very  hard  dark  gray  clay  which  slakes  very  slowly.  However,  when 
properly  worked  with  sufficient  water,  it  develops  a fair  degree  of  plasticity  and 
may  be  forced  through  a die  satisfactorily. 

Water  of  plasticity per  cent  20.7 

Shrinkage  water  per  cent  9.1 

Pore  water  per  cent  11.6 

Modulus  of  rupture  lbs.  per  sq.  in.  295.6 

Slaking  test,  average min.  8 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  4.9 

Linear;  wet  length 4.7 

Volume  17.6 

Burning  test : — 


Cone 

02 

Porosity 
Per  cent 
20 

Color 

Cream  

Burning 
shrinkage 
Per  cent 
2.8 

Remarks 

2 

17.3 

Cream  

4.7 

5 

13.8 

Cream  

8.3 

9 

6.8 

Cream 

11.0 

Fine  iron  spots 

12 

2.5 

Gray  white 

11.5 

Fine  iron  spots 

13 

1.5 

Grayish  white 

10.5 

Numerous  iron  spots, 

small 

15 

4.0 

Grayish  white  

Numerous  iron  spots ; 

slagged 

Fusion  test: — No  deformation  at  cone  30. 

No  vesicular  structure. 

Note: — The  iron  (?)  spots  are  so  black  as  to  suggest  the  presence  of  manganese. 
Its  unusual  appearance  may  be  due  to  reduction.  The  effect  at  higher  cones  is  very 
unique  and  interesting. 


The  clay  has 
shrinkage  at 


Summary 

a medium  strength.  The  drying  shrinkage  is  medium  low.  Total 
cone  9 is  medium  high.  Minimum  porosity.  Complete  vitrification  is 


112 


ILLINOIS  FIRE  CLAYS 


reached  at  cone  13.  At  cone  15  the  slight  increase  in  porosity  may  indicate  incipient 
overburning.  It  is  a refractory  clay. 

Suggested  uses : The  appearance  of  numerous  fine  slagged  spots  at  the  high 
temperatures  raises  a question  as  to  the  desirability  of  this  as  a material  for  re- 
fractories. Its  slow  slaking  character  lessens  its  value  in  some  degree  for  stoneware 
and  architectural  terra  cotta.  However,  weathering  or  aging  will  correct  these 
difficulties. 

FULTON  COUNTY 

A sample  of  clay  (No.  84)  from  about  a mile  northwest  of  Avon  was 
taken  at  the  Avon  Milling  and  Manufacturing  Company’s  plant  at  Avon. 
The  clay  had  been  dug  from  the  bed  of  Swan  Creek  and  is  used  for  refrac- 
tory linings  about  the  boiler. 


RESULTS  OF  TESTS 
FULTON  COUNTY 


Sample  No.  84 

(Avon  Milling  and  Manufacturing  Company,  at  Avon) 

The  clay  is  a dark  gray  color  with  darker  patches  due  to  the  presence  of  car- 
bonaceous matter.  Its  plasticity  is  only  fair  and  its  conduct  in  flowing  through  a 


die  is  fair. 

Water  of  plasticity  per  cent  21.5 

Shrinkage  water  per  cent  9.0 

Pore  water  . . . . : per  cent  12.4 

Modulus  of  rupture  lbs.  per  sq.  in.  214 

Slaking  test,  average  min.  Al/2 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 

40 0.5  Sand  and  coal 

60 3.2  Sand  and  coal 

80 0.4  Sand  and  coal 

120 2.3  Sand  and  coal 

200 11.6  White  sand,  mica,  and 

coal 


Drying  shrinkage : — 

Per  cent 

Linear ; wet  length  3.7 

Linear ; dry  length  3.8 


Volume  . . . 
Burning  test: — 


Cone 

2 

3 

6 

9 

13 

15 


Porosity 
Per  cent 
26 
26 
25 
20 
11.6 
16.6 


Burning 

Color  shrinkage 

Per  cent 

Light  tan  1.8 

Light  tan  1.9 

Light  tan  2.6 

Light  tan  3.7 

Buff  5.5 

Buff  5.8 


Remarks 

Granular  fracture 
Granular  fracture 
Granular  fracture 
Granular  fracture 
Fine  iron  ( ?)  spots 
Fine  iron  (?)  spots 


Fusion  test : — The  cone  fused  to  a glass  at  cone  28. 


FULTON  AND  MERCER  COUNTIES 


113 


Summary 

The  strength  of  the  clay  is  medium.  There  is  a considerable  amount  of  residue 
left  on  the  screens.  The  drying  shrinkage  is  medium  low,  and  when  burned  at  cone 
9,  the  total  shrinkage  is  medium  low.  Vitrification  is  incomplete  at  cone  13  and  it  is 
overburned  at  cone  15.  It  is  a non-refractory  clay. 

Suggested  uses:  Architectural  terra  cotta,  face  brick.  It  appears  to  be  rather 
short  for  stoneware. 

MERCER  COUNTY 

The  Northwestern  Clay  Manufacturing  Company  formerly  recovered 
small  amounts  of  clay  with  the  No.  1 coal  at  their  pits  near  Griffin.  A 
sample  was  taken  from  clay  which  had  been  drawn  from  below  the  No.  1 
coal  at  that  time.  The  shale,  till,  and  overlying  soil  are  used  for  sewer  pipe. 

Section  of  the  Northwestern  Clay  Manufacturing  Company's  pit  at  Griffin 


Thickness 
Ft.  In. 

6 Soil  and  yellow  clay 10 

5.  Shale  (Sample  No.  86) 25  to  30 

4.  Limestone  2 

3.  “Potter’s  clay,”  thin  horizon unmeasured 

2.  Coal  (No.  1) 2 5 

1.  Clay  (Sample  No.  85)  6 


RESULTS  OF  TESTS 
MERCER  COUNTY 

Sample  No.  86 

(Northwestern  Clay  Manufacturing  Company’s  pit,  at  Griffin) 

The  material  is  a hard  grayish-colored,  shaly  clay,  streaked  with  brown  and 
black.  The  plasticity  is  fair. 


Water  of  plasticity per  cent  29.5 

Shrinkage  water per  cent  21.9 

Pore  water  per  cent  7.6 

Modulus  of  rupture lbs.  per  sq.  in.  190.2 

Slaking  test,  average  min.  6 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 

10 2.2' 

14 1.7 

20 2.4 

35 3.2  ► Particles  of  shale,  grains 

48 0.6  of  coal 

65 0.4 

100 1.1 

150 1.0  Shale  with  mica 

200 1.5  Shale  with  mica 

Drying  shrinkage : — 


Linear ; dry  length 
Linear ; wet  length 


Per  cent 
. . 3.62 
..  3.5 


114 


ILLINOIS  FIRE  CLAYS 


Burning  test : — 

Cone  Porosity 

Color 

Burning 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

18.4 

Dark  red  

5.0 

Hackly  fracture 

5 

14.5 

Dark  red  

8.5 

9 

0.5 

Dark  red  

9.4 

Vitreous  fracture 

12 

Bloated 

Fusion  test : — It  fused  completely  at  cone  27. 


Summary 

The  drying  shrinkage  is  medium  low.  The  strength  is  medium  low.  The  total 
shrinkage  at  cone  9 is  medium  high.  The  shale  reaches  a minimum  porosity  at  or 
before  cone  9 and  overburns  beyond  that  point. 

Suggested  uses : Sewer  pipe,  brick,  tile,  etc. 


Sample  No.  85 

(Northwestern  Clay  Manufacturing  Company’s  pit,  at  Griffin) 

The  sample  is  a soft  clay  of  a gray  color  with  darker  mottling.  Its  plasticity 


is  very  good  when  tempered  with  water. 

Water  of  plasticity  per  cent  28.8 

Shrinkage  water  per  cent  11.9 

Pore  water per  cent  17.0 

Modulus  of  rupture lbs.  per  sq.  in.  386.7 

Slaking  test,  average  min.  Al/i 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 


10 7.0' 

14 6.5 

20 8.9 

35 13.8-  Particles  of  coal  and 

48 3.7  shale 

65 5.4 

100 3.9 

150 2.4'  Particles  of  coal  and 

200 2.6  - shale,  with  flakes  of 

mica 


Drying  shrinkage,  linear  per  cent  6.5 

Volume per  cent  21 

Burning  test : — 

Total 

Cone  Porosity  Color  shrinkage  Remarks 

Per  cent  Per  cent 

02  14.4  Cream  13.4  

1 6.7  Cream  14.6  

3 0.5  Gray  15.9 

5 0.8  Dark  gray  16.2 

7 1.2  Dark  gray  13.6 


13 


1.4 


1.6 


Dark  gray 
Dark  gray 


11.1 


7.5 


Vitrified 
Bluestoned 
Bluestoned ; 

vesicular 
Bluestoned ; 

vesicular 
Bluestoned  ; 
vesicular 


slightly 

slightly 

slightly 


Fusion  test : — Completely  deformed  at  cone  26.  Vesicular. 


ROCK  ISLAND  COUNTY 


115 


Summary 

The  strength  of  the  clay  is  medium.  The  quantity  of  screen  residues  is  high. 
The  drying  shrinkage  is  medium.  The  total  shrinkage  at  cone  5 is  medium  high. 
Complete  vitrification  is  attained  at  a very  low  cone  and  the  incipient  overburning 
which  seems  to  appear  at  cone  9 does  not  become  serious  even  at  cone  16.  The 
appearance  of  the  pieces  suggests  reducing  conditions  during  the  burn.  The  appear- 
ance of  a whitewash  on  the  pieces  burned  at  cone  7 or  lower  should  be  noted.  It 
is  non-refractory. 

Possible  uses : Architectural  terra  cotta,  paving  brick,  stoneware,  sanitary  ware, 
sewerpipe,  conduits. 

ROCK  ISLAND  COUNTY 

A sample  was  taken  from  the  clay  above  No.  1 coal  at  Sears  (sample 
No.  83).  The  clay  below  that  coal  was  covered  by  water  when  visited.  A 
second  sample  was  taken  from  white  clay  lying  directly  below  the  No.  1 
coal  (sample  No.  81)  ; ordinarily  a 5-foot  sandstone  commonly  separates 
this  clay  and  the  coal  but  here  it  is  missing.  The  clay1  is  full  of  pyrite 
concretions  which  weather  to  limonite  at  the  surface.  The  plant  which 
formerly  operated  here  is  now  idle  and  the  pits  are  in  bad  condition. 

Results  of  tests  on  samples  No.  83  and  No.  81  are  given  on  pages 
115  and  116. 

A large  part  of  the  upper  40  feet  of  the  overburden  which  is  a fine 
loess  of  pure  quartz  sand  is  now  used  for  moulding  sand.  The  value  of 
the  overburden  in  this  case  would  materially  reduce  the  cost  of  obtaining 
the  clay  if  it  were  to  be  worked  from  an  open  cut.  The  maximum  over- 
burden would  be  nearly  60  feet. 

At  Carbon  Cliff  the  fine  clay  (Cheltenham)  varies  from  10  to  25  feet 
in  thickness,  being  replaced  where  the  lesser  thickness  is  found  by  as  much 
as  10  feet  of  black  shale  which  apparently  wedges  out  laterally  into  the  clay. 
The  clay  shows  iron  stains  and  traces  of  red.  At  its  base  there  is  a layer 
of  nodular  impure  limestone  boulders  and  limonite  concretions.  The  over- 
burden of  18  to  25  feet  could  be  removed  most  economically,  it  is  believed, 
by  a steam  shovel. 

Sample  No.  79  was  taken  from  the  west  bank  and  sample  No.  80  from 
the  working  face  in  the  east  pit.  Results  of  tests  are  on  page  117. 

RESULTS  OF  TESTS 
ROCK  ISLAND  COUNTY 

Sample  No.  83 

(Clay  above  No.  1 coal  at  Sears) 

This  is  a medium  hard  clay  which  is  colored  gray,  heavily  mottled  with  brown. 
The  plasticity  is  very  good  when  it  is  tempered  with  water  and  it  flows  satisfactorily 
through  a die. 

Water  of  plasticity per  cent  28.7 

Shrinkage  water  Per  cent  16.4 

Pore  water per  cent  12.2 


lAccording  to  Lines,  Op.  cit.,  this  clay  was  formerly  used  for  sewer  pipe. 


116 


ILLINOIS  FIRE  CLAYS 


Modulus  of  rupture,  maximum lbs.  per  sq.  in.  768 

minimum lbs.  per  sq.  in.  664 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  329 

Slaking  test,  average  min.  11  x/2 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  7.5 

Linear ; wet  length  7.0 

Volume  31.2 

Burning  test: — 


Cone 

Porosity 

Color 

Burning 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04 

28.0 

Pinkish  red  

1.0 

02 

15.0 

Pinkish  tan  

5.1 

Hackly  fracture 

2 

1.1 

6.7 

Hackly  fracture 

5 

2.2 

Dark  tan  

6.8 

Glossy  fracture 

9 

1.6 

Dark  tan  

6.5 

Smooth  vitreous  frac- 

ture 

13 

12.0 

Gray  

4.5 

Overburned 

Fusion  test: — It  entirely  fused  at  cone  27. 

Summary 

The  strength  of  the  clay  is  medium  high  and  its  bonding  strength  is  medium. 
The  drying  shrinkage  is  medium.  The  total  shrinkage  at  cone  9 is  medium.  Vitrifi- 
cation proceeds  very  rapidly  between  cones  02  and  2,  at  which  temperature  it  is 
practically  complete.  It  is  overburned  between  cones  9 and  13.  It  is  non-refractory. 

Suggested  uses : Face  brick,  paving  brick,  sewer  pipe,  drain  tile.  The  color  of 
the  burned  material  is  rather  dark  for  stoneware  or  terra  cotta. 

Sample  No.  81 

(Clay  below  No.  1 coal  at  Sears) 

This  is  a soft  gray  colored  clay,  streaked  with  brown  and  containing  a few 
black  spots.  It  contains  much  mica. 

Water  of  plasticity  per  cent  22.6 

Shrinkage  water per  cent  9.8 

Pore  water per  cent  12.7 

Slaking  test,  average min.  8 

Drying  shrinkage  : — 

Per  cent 

Linear  5.2 

Volume 17.8 

Burning  test: — 

Total 

Remarks 


Total 

Cone 

Porosity 

Color 

shrinkage 

Per  cent 

Per  cent 

1 

13.7 

Brown  

8.7 

5 

6.1 

Dark  brown 

11.8 

9 

2.4 

Dark  brown 

11.2 

15 


Bloated  badly 


Fusion  test: — Completely  fused  at  cone  26  to  brown  glass  showing  a partly  vesicular 
structure.  Summary 

The  drying  shrinkage  is  medium  low  and  vitrification  is  practically  complete  at 
cone  9.  It  is  overburned  between  that  cone  and  cone  15.  It  is  non-refractory. 
Suggested  uses : Brick,  tile. 


ROCK  ISLAND  COUNTY 


117 


Sample  No.  79 
(West  bank  at  Carbon  Cliff) 


This  is  a soft  clay  having  a dark  gray  color  with  some  brown  streaks.  When 
tempered  with  water  it  becomes  very  plastic.  It  flows  fairly  well  through  a die. 


Water  of  plasticity 

Shrinkage  water  

Pore  water  

Modulus  of  rupture 

With  50%  standard  sand — Modulus  of  rupture. . . . 

Slaking  test,  average  

Screen  test : — 

Mesh 

20 

Residue 
Per  cent 

Character  of 
residue 

40 

60 

80 

120 

200 

...  1.8 

Sand  and  mica 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  

6.6 

Linear;  wet  length  

6.2 

Volume  

Burning  test: — 

Burning 

Cone  Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04  32 

Cream  

...  0.0 

02  32 

Cream  

. . . 1.0 

Hackly  fracture 

2 28 

Cream  

. . . 1.5 

Hackly  fracture 

5 28 

Cream  

. . . 2.0 

Hackly  fracture 

9 23 

Cream  

. . . 3.1 

Hackly  fracture 

13  18 

Cream  

. . . 3.6 

Granular  fracture 

14  6 

Brown  exterior;  bluestoned. 

. . . 2.8 

Fusion  test : — It  fuses  entirely  at  cone  26.  No  vesicular  structure. 


Summary 

The  clay  has  a medium  strength  and  a medium  low  bonding  strength.  The 
drying  shrinkage  is  medium  and  the  total  shrinkage  at  cone  9 is  medium.  The  clay 
is  very  open  burning  until  cone  14  is  reached.  It  is  non-refractory. 

Suggested  uses : Architectural  terra  cotta,  stoneware,  sanitary  ware,  and  face 

brick. 


Sample  No.  80 
(East  pit  at  Carbon  Cliff) 

This  is  a clay  of  a medium  degree  of  hardness,  colored  gray  with  a darker 
mottling.  It  develops  a good  degree  of  plasticity  when  tempered  with  water  and 
flows  satisfactorily  through  a die. 


118 


ILLINOIS  FIRE  CLAYS 


Water  of  plasticity 

Shrinkage  water 

Pore  water  

Modulus  of  rupture 
Slaking  test,  average 
Drying  shrinkage,  linear 
Volume  


Per  cent  20.5 

per  cent  9.2 

per  cent  11.3 

lbs.  per  sq.  in.  445.4 

min.  10^2 

per  cent  6.2 

per  cent  17.7 


Burning  test: — 

Total 


Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

20.7 

Cream  

7.2 

1 

19.7 

Cream  

7.5 

3 

16.4 

Cream  

8.1 

Hackly  fracture 

5 

13.4 

Gray  

8.6 

Hackly  fracture 

8 

10.4 

Gray  

10.0 

9 

7.2 

Gray  

9.8 

Vitrified ; hackly  frac- 

ture 

13 

7.5 

Gray  

9.7 

Conchoidal  fracture 

Fusion  test: — Test  pieces  are  % deformed  at  cone  26  and  slightly  vesicular. 


Summary 

The  clay  has  a medium  high  strength  and  medium  shrinkage  at  cone  9.  The 
total  shrinkage  is  medium.  Vitrification  is  still  incomplete  at  cone  13.  The  clay 
borders  on  the  refractory  type. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  refractories,  face  brick. 


LA  SALLE  COUNTY 

At  the  pits  of  the  Utica  Firebrick  and  Clay  Company  two  miles  south 
of  Utica  the  section  is  variable,  but  a somewhat  generalized  section  of  the 
east  pit  (fig.  55)  is  as  follows: 


Sections  of  the  east  pits  of  the  Utica  Firebrick  and  Clay  Company 
2 miles  south  of  Utica 

Thickness 

Ft.  In. 


6.  Overburden,  glacial  drift  and  soil 12 

5.  Coal  (No.  1)  1 6 

4.  Clay,  blue,  “Joliet  clay”  (Sample  No.  87,  p.  125)  ; the  upper  foot 
contains  numerous  pyrite  concretions,  and  similar  concretions 

are  found  in  the  lower  Ibeds 3 6 

3.  Clay,  green  8 

2.  Clay,  gray,  jointed  (Sample  No.  77,  p.  126)  ; used  for  fire  brick;  the 
upper  3 feet  has  a few  small  pyrite  seams  and  concretions 
(av.  8 ft.)  ; at  one  place  2 feet  of  the  residual  basal  clay  is 

lighter  in  color  grading  into  a darker  clay  above 4 10 

1.  Sandstone,  St.  Peter;  forms  the  “nigger  heads”  of  the  mines;  the 
surface  of  the  sandstone  is  very  uneven  and  in  one  place  rises 
so  that  the  clay  is  only  1 Yi  feet  thick 


LA  SALLE  COUNTY 


119 


A second  section  of  East  pit  of  the  Utica  Firebrick  and  Clay  Company 

Thickness 


Feet 

3.  Soil  and  drift 2 to  5 

2.  Clay,  dark  gray,  with  scattered  pebbles  and  some  conglomerate 10* 

1.  Conglomerate,  highly  weathered,  heavy 


Sample  No.  82  from  the  east  pit  was  lost  in  transit,  and  H.  E.  Culver 
of  the  Survey  staff  visited  the  pit  later  with  the  intention  of  taking  a sub- 


Fig.  55.  View  of  the  Utica  Firebrick  and  Clay  Company’s  pit  south  of  Utica;  No.  2 coal 

overlies  the  clay. 


stitute  sample.  Being  unable  to  find  the  exact  location  from  which  sample 
No.  82  had  been  taken,  he  measured  the  following  section  and  took  sample 
No.  C 82 ; results  of  tests  are  given  on  pages  126  and  127. 

Section  of  West  pit  of  the  Utica  Firebrick  and  Clay  Company, 
near  Utica 

4.  Overburden,  soil  and  drift 2 to  5 

3.  Clay,  gray,  yellow  when  first  exposed,  very  tough 2 to  3 

2.  Clay,  darker  yellow,  “putty  clay”  (Sample  No.  82)  ; chert  concre- 
tions and  pyrite  at  base  5 to  6 

1.  Sandstone;  very  much  hardened  by  iron  at  surface 

The  clay  is  hauled  by  train  from  the  pit  to  a tipple,  dumped  down  onto 
a tram  at  river  level,  transferred  across  the  Illinois  River  by  barge  and  then 
taken  by  train  to  the  plant  at  Utica. 


120 


ILLINOIS  FIRE  CLAYS 


About  20  acres  has  been  tested  by  drilling  beyond  the  borders  of  the 
present  pits. 

The  plant  can  produce  from  12,000  to  20,000  fire  brick  per  day  and 
about  30  tons  of  ground  fireclay  is  shipped  every  month  as  well  as  crude 
clay  in  varying  amounts  up  to  1000  tons.  Small  lots  of  the  yellow  “putty” 
clay  have  been  shipped  for  ochre  but  most  of  it  is  used  as  furnace  lining. 
A boring  between  the  two  pits  has  shown  that  the  “putty”  clay  overlies  the 
better  grade  blue  clay. 

M.  J.  Gorman  and  Company  are  operating  an  open  pit  in  sec.  21,  T.  22 
N.,  R.  1 E.  The  clay  is  hauled  \ l/2  miles  by  team  and  wagon  to  Utica.  The 
average  production  is  about  10,000  tons  per  year,  including  both  “putty”  and 
blue  clay. 


Section  of  M.  J.  Gorman  and  Company's  pit  V/2  miles  south  of  Utica 


9. 

8. 

7. 

6. 

5. 

4. 

3. 

2. 

1. 


Soil  

Soil  and  drift 

Coal  (No.  2),  absent  over  parts  of  the  clay 

Clay,  yellow  and  blue,  very  plastic,  scattered  gypsum  crystals ; 

clay”  (Sample  No.  97,  pp.  127-128) 

Clay,  green  

Clay,  blue  (Sample  No.  100,  pp.  128-129) 

Pyrite,  large  boulders,  usually  with  calcareous  centers 

Clay,  blue  

Sandstone,  probably  St.  Peter 


Thickness 
Ft.  In. 

1 

6 

3 

“putty 

4 

6 


9 


5 


Sample  No.  98  was  taken  from  the  side  of  a gully  a few  rods  up-stream 
from  the  mouth  of  the  clay  pit.  It  lies,  however,  below  the  mouth  of  the 
pit  in  altitude.  This  is  not  worked,  and  the  sample  was  taken  from  a 
2'  x 4'  x 3"  cut  on  the  sloping  surface  of  the  clay  bank  which  lies  beneath 
soil  and  above  sandstone  which  is  probably  St.  Peter,  but  may  be  the  lower 
sandstone  of  the  Pennsylvanian.  See  page  129  for  results  of  tests. 

More  than  seventy  acres  of  clay  have  been  proved  by  boring. 

The  Company  is  contemplating  tractor  and  trailer  haulage  over  the  1 V2 
miles  of  paved  road  to  the  railroad  at  Utica. 

The  Illinois  Clay  Products  Company  are  producing  250  to  300  tons  of 
ground  fireclay  per  day,  from  their  mine  at  Deer  Park. 

Only  the  upper  6 or  7 feet  is  mined  at  the  present  time,  as  it  is  found 
impracticable  to  mine  a greater  thickness. 


LA  SALLE  COUNTY 


121 


Section  of  Illinois  Clay  Products  Company's  mine  at  Deer  Park 


Thickness 
Ft.  In. 

10.  Overburden,  of  glacial  till  and  soil unmeasured 

9.  “Soapstone,”  compact,  sandy  clay  shale 15± 

8.  Coal  (No.  2);  forms  roof  of  mine 3 6 


7.  Clay  (Sample  No.  93,  p.  130)  ; only  thej  upper  6 to  7 feet  mined  at 
present;  erratic  lenses  of  sandrock  at  the  bottom  of  the  present 
workings;  pyrite  nodules  about  3 feet  from  the  top  of  the  clay, 
also  large  pisolitic  boulders ; in  part  of  mine,  clay  rests  on  St. 

Peter  sandstone  and  possibly  in  other  part  on  “Trenton”  lime- 
stone   13 

Outside  the  mouth  of  the  mine  lower  beds  are  exposed  as  follows : 

6.  Sandstone,  thin  layer  3 

5.  Clay,  coal  and  coaly  shale  (No.  1 [?]) 6 

4.  Fireclay,  very  fine  textured,  plastic,  and  light  in  color  (Sample 

No.  96,  p.  131) 4 

3.  Fireclay,  sandy  2 

2.  Pyrite  bed,  less  than  2 

1.  Limestone,  Trenton  

The  clay  is  hauled  by  train  and  electric  motor  to  the  mill  and  after 
grinding  is  carried  by  cable  train  across  the  Big  Vermilion  River  to  the 
Rock  Island  Railroad. 

At  Lowell  the  clay  below  the  No.  2 coal  has  been  used  in  a small  way 
for  pottery  at  the  Lowell  Stoneware  Company’s  plant. 

Section  of  the  Lowell  Stoneware  Company’s  pit  at  Lowell 

Thickness 


Feet 

4.  Overburden,  drift  and  soil  1 to  12 

3.  Coal  (No.  2)  ZV2 

2.  Clay  (Sample  No.  90,  p.  132),  dark  gray  to  light  drab  “W”  clay;  the 
upper  three  feet  contains  much  pyrite  at  the  base  of  which  there 

are  locally  traces  of  green  coloring 12  to  25 

1.  Limestone,  Trenton  


Preliminary  drilling  is  said  to  have  proved  that  the  clay  underlies  at  least 
200  acres.  A great  part  of  this  is  overlain  by  an  overburden  of  less  than 
15  feet  and  could  easily  be  removed  by  steam  shovel. 

Near  the  river  bank  small  quantities  of  clay  have  been  dug  from  directly 
beneath  1 to  7 feet  of  soil  and  drift  overburden.  The  clay  here  is  distinctly 
bedded  and  of  a gray  color  with  an  occasional  yellow  pocket.  It  is  sold  as 
the  “R”  clay  (sample  No.  89,  p.  132). 

The  Pennsylvanian  rocks  are  missing  on  the  east  flank  of  the  La  Salle 
anticline  at  Utica.  The  bluffs  of  Illinois  Valley  are  largely  St.  Peter  sand- 
stone from  Utica  to  Twin  Bluffs  on  the  south  side  of  Illinois  River.  At  Twin 
Bluffs  the  National  Fireproofing  Company  is  working  clay  in  open  cut  from 
directly  above  the  St.  Peter  sandstone,  and  about  a mile  to  the  east  the 


122 


ILLINOIS  FIRE  CLAYS 


Herrick  Clay  Manufacturing  Company  is  tunneling  the  clay  (sample  No. 
95,  p.  133)  from  the  same  horizon.  A section  of  the  face  of  the  former  pit 
is  given  here: 


Section  of  National  Fireproofing  Company’s  pit  at  Twin  Bluffs 


5. 

4. 

3. 

2 

1. 


Thickness 
Ft.  In. 


Overburden,  drift  unmeasured 

Shale  (“Soapstone”)  8 

Coal  (No.  2)  1 11 

Shale,  black 6 

Clay  (Sample  No.  94,  p.  134)  ; lighter  in  color  and  more  sandy 
toward  the  bottom  7 


At  the  Herrick  mine  the  clay  is  8 feet  thick  and  because  of  the  east- 
ward dip  the  overlying  shale  has  increased  to  more  than  30  feet.  At  the 
National  Fireproofing  pit  the  drift  overburden  and  the  shale  are  used  for 
drain  tile  and  building  blocks.  The  coal  above  the  clay  is  also  recovered. 
At  both  plants  the  clays  are  ground  and  shipped.  The  output  from  the 
National  Fireproofing  plant  is  approximately  800  tons  per  week  and  a similar 
or  somewhat  lesser  quantity  is  shipped  from  the  Herrick  mine. 


At  Ottawa  the  Fox  and  Illinois  rivers  have  cut  through  the  Pennsyl- 
vanian and  are  now  flowing  on  St.  Peter  sandstone.  About  2 miles  east  of 
that  city  basal  Pennsylvanian  clay  is  dug  from  two  open  pits ; that  of  the 
Chicago  Retort  and  Firebrick  Company  and  that  of  the  National  Fire- 
proofing Company. 


10. 

9. 

8. 

7. 

6. 

5. 

4. 

3. 

2. 

1. 


Section  of  the  National  Fireproofing  Company’s  “Pioneer’’  pit 
2 miles  east  of  Ottawa 


Thickness 
Ft.  In. 


Soil  

Shale  (“soapstone”)  16 

Coal  2 

Fireclay,  dark  1 

Fireclay,  lighter  gray  (Sample  No.  91,  p.  135)  ; lenses  of  large 
rounded  pisolitic  boulders  which  contain  large  amounts  of  pyrite  8 

Clay,  green,  in  lenses,  local 

Sandstone,  hard,  brown  1 to  4 

Clay,  very  light  in  color  (Sample  No.  92,  p.  136) 5 to  9 

Clay,  sandy 1 

Sandstone,  St.  Peter  


6 

2 


2 


The  clay  is  dug  by  steam  shovel  and  hauled  by  electric  tram  to  the  plant 
at  Ottawa.  The  output  is  about  5000  tons  of  manufactured  ware  per  month, 
chiefly  hollow  ware  and  fire  brick,  and  1000  tons  of  ground  fireclay. 


LA  SALLE  COUNTY 


123 


Section  of  the  Chicago  Retort  and  Firebrick  Company’s  pit 
northeast  of  Ottazva 

Thickness 
Ft.  In. 


8.  Soil  1 

7.  Shale,  blue,  weathers  light;  “soapstone” . ..  17 

6.  Shale,  darker ; colored  by  carbon  2 

5.  Coal 2 

4.  Gypsum,  persistent  layer  1 

3.  Clay,  colored  by  carbon  2 


2.  Fireclay  (Sample  No.  101,  p.  136)  ; traces  of  green  in  lower  beds 
where  clay  becomes  lighter  in  color ; large  rounded  sandy  pyritic 
boulders  in  bottom  of  pit ; smaller  pyrite  concretions  scattered  in 
the  clay  4 to  8 

1.  Sandstone,  St.  Peter  

This  section  differs  little  from  the  preceding  one,  except  that  instead 
of  the  lower  clay  it  has  the  green  clay  resting  directly  upon  the  St.  Peter 
sandstone.  A large  area  of  this  clay  has  been  removed,  but  the  Company 
reports  holdings  of  300  acres  of  tested  reserve  clay  land  east  and  north  of 
the  present  pit.  No  use  is  made  of  the  overburden  which  is  removed  by 
steam  shovel  and  tram. 

Three  grades  of  clay  are  used:  (1)  Raw  clay  from  this  pit;  (2)  raw 
clay  blended  with  Missouri  flint  clay;  and  (3)  raw  clay  blended  with  a mix- 
ture of  raw  and  calcined  Missouri  flint  clay. 

About  half  a mile  southeast  of  Dayton,  clay  is  mined  from  a tunnel 
driven  in  the  side  of  a deep  ravine. 

Section  at  Dayton  Clay  Works  half  a mile  south  of  Dayton 

Thickness 


Feet 

6.  Loam,  drift,  and  soil  6 

5.  Shale,  more  compact  toward  the  base 32 

4.  Shale,  dark  blue  1 

3.  Coal  (No.  2) 

2.  Clay,  sandy,  pyritic  gray  (Sample  No.  99,  p.  138) 4^2  to  5^2 

1.  Sandstone  


Sample  No.  102  (p.  138)  was  from  an  outcrop  of  the  gray  fireclay 
above. 

The  clay  is  ground  and  loaded  by  elevated  conveyor  onto  a switch  of 
the  Chicago,  Burlington  and  Quincy  Railroad  about  100  yards  east  of'  the 
plant. 

The  Chicago  Firebrick  Company  is  reopening  the  entries  of  the  old 
Spicer  Coal  Company’s  mine  2 miles*  east  of  Marseilles  with  the  intention 
of  obtaining  the  clay  which  here  is  at  a depth  of  about  90  feet.  The  clay 
is  worked  from  a new  face  at  the  outer  margin  of  the  former  mine  by  the 
room  and  pillar  system. 


124 


ILLINOIS  FIRE  CLAYS 


Section  of  Chicago  Firebrick  Company's  shaft  2 miles  east  of  Marseilles 

Thickness 

Feet 

Shaft  from  top  of  coal  to  surface 90  =*= 

4.  Coal  (No.  2)  zy2 

3.  Fireclay,  drab,  comparatively  free  from  pyrite  but  colored  by  carbon.  .Zl/2  to  6 

2.  Clay,  green ; rich  in  pyrite  y2  to  3 

1.  Fireclay;  pyrite  in  small  crystals  to  bottom  of  present  workings;  a 
maximum  of  12  feet  of  this  lower  clay  has  been  penetrated;  at 
the  shaft  the  St.  Peter  sandstone  is  8 feet  4 inches  below  the  bot- 
tom of  the  coal  5 

The  clay  is  shipped  as  ground  clay. 

Sample  No.  129  was  taken  from  the  working  face  omitting  the  green 
clay.  (See  page  140). 

South  and  east  from  Utica,  or  away  from  the  crest  of  the  La  Salle 
anticline,  the  base  of  the  Pennsylvanian  beds  lowers  and  in  only  a few 
places  have  mine  shafts  penetrated  to  the  level  of  the  clay. 

Two  miles  south  of  Streator,  the  shaft  of  the  Streator  Clay  Manufac- 
turing Company  penetrates  the  No.  2 coal,  but  the  underlying  clay  is  not 
of  as  good  a quality  as  that  farther  north. 

Section  of  Streator  Clay  Manufacturing  Company’s  shaft 


2 miles  south  of  Streator 

Thickness 
Ft.  In. 

Shaft 230 

4.  Coal  (No.  2)  2 6 

3.  Fireclay,  gray  and  blue  (Sample  No.  130-a,  p.  140) l1/3to4 

2.  Clay,  sandy,  “sandrock”  3 to  5 

1.  Clay,  greenish  gray;  “Intermediate  clay”  (Sample  No.  130-b, 

p.  140)  2 6 

Bottom  not  reached. 


At  Kangley  the  Spring  Lake  Coal  Company  is  mining  the  No.  2 coal. 
Clay  brought  out  in  lifts  from  digging  sumps  was  sampled  from  the  dump. 
Results  of  tests  on  the  sample  (No.  131)  are  given  in  page  140. 


Section  of  the  Spring  Lake  Coal  Company’s  shaft  at  Kangley 


4 miles  northwest  of  Streator 

Thickness 

Feet 

Shaft  * 200 

2.  Coal  (No.  2)  3 

1.  Clay  (Sample  No.  131)  ; bluish  and  greenish  gray  with  small  gypsum 

crystals  and  an  occasional  iron  stain 5 

Bottom  not  reached. 


I A SALLE  COUNTY 


125 


RESULTS  OF  TESTS 
LA  SALLE  COUNTY 


Sample  No.  87 

(East  pit  of  the  Utica  Firebrick  and  Clay  Company ; 

2 miles  south  of  Utica) 

This  clay  is  of  medium  hardness.  It  is  of  a dark  gray  or  slate  color  speckled 
with  a few  black  spots.  The  plasticity  is  very  high  when  it  is  tempered  with  water, 
and  its  conduct  when  flowing  through  a die  is  good. 

Water  of  plasticity per  cent  25.6 

Shrinkage  water  per  cent  17.0 

Pore  water  ,per  cent  8.6 

Modulus  of  rupture lbs.  per  sq.  in.  497.6 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  290.3 


nun. 


10.5 


Slaking  test,  average 
Screen  test : — 

Mesh 


20 None 

40 

60 

80 

120 

200 

Drying  shrinkage : — 


Linear;  wet  length  8.5 

Volume  34.5 

Burning  test : — 

Color 


Cream,  nearly  white 3.1 

Light  cream  4.2 

White  exterior 

Cream  5.1 


Residue 
Per  cent 

Character  of 
residue 

. . T race  

. 0.4 

Fine  white  sand 

. 0.2 

Fine  white  sand 

. 0.7 

Fine  white  sand 

. 0.9 

Fine  white  sand 

Per  cent 

9.3 

Cone 

Porosity 
Per  cent 

02 

17.0 

2 

12.3 

4 

10.7 

8 

8.4 

9 

8.2 

12 

4.7 

14 

5.0 

Cream  5.1 


Burning 
shrinkage 
Per  cent 

. . 3.1 

Remarks 

..  4.2 

Fine  iron  spot 

Fine  iron  spot 

..  5.1 

Numerous  fine 
spots 

iron 

..  5.1 

Numerous  fine 
spots 

iron 

..  5.8 

Numerous  fine 
spots 

iron 

..  5.6 

Numerous  fine 

iron 

spots,  slagged 


Oxidation  conduct : — Appears  to  be  very  slow. 
Fusion  test: — Deforms  at  cone  28. 


Summary 

The  strength  of  the  raw  clay  is  medium  high  and  its  bonding  strength  is  high. 
The  amount  of  residue  on  the  sieves  is  slight.  The  drying  shrinkage  is  medium  and 
the  total  shrinkage  at  cone  9 is  medium  high.  Vitrification  is  incomplete  at  cone  14. 
Oxidation  appears  to  have  been  very  slow.  It  is  a refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  face  brick, 
refractories. 


126 


ILLINOIS  FIRE  CLAYS 


Sample  No.  77 

(East  pit  of  the  Utica  Firebrick  and  Clay  Company;  2 miles  south  of  Utica) 

This  is  a very  hard  dark  gray  colored  clay.  When  powdered  and  tempered  with 
water,  it  develops  a fair  degree  of  plasticity  and  will  flow  through  a die  satisfactorily. 

Water  of  plasticity  per  cent  19.8 

Shrinkage  water  per  cent  9.3 

Pore  water  per  cent  10.5 

Modulus  of  rupture lbs.  per  sq.  in.  320 

With  50%  standard  sand — Modulus  of  rupture  lbs.  per  sq.  in.  261 

Slaking  tests,  average  min.  9 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 


oi] 
0.2 
1.0 
1.8  | 
1.21 


Quartz  and  pyrite 


20 

40 

60 

120 

200 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  7.5 

Linear ; wet  length 7.0 

Volume 19.2 

Drying  conduct : — Efflorescence,  i.  e.,  “whitewash,”  appears  at  the  corners  of  the  sample. 
Burning  test : — 

Burning 


Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

14.4 

Cream  

4.4 

Granular  fracture 

3 

11.0 

Cream  

4.8 

Granular  fracture 

6 

vn 

00 

Darker  cream  

5.4 

Granular  fracture 

8 

5.1 

Grayish  

5.5 

Granular  fracture 

9 

4.4 

Grayish 

5.1 

12 

6.0 

Bluestoned 

4.3 

1254 

Tan,  light  bluestoned  

15 

5.0 

Buff  exterior ; bluestoned, 

black  3.6 

Some  iron  spots 

Fusion  test: — Cone  Y deformed  at  cone  28.  Vesicular  structure. 

Summary 

The  clay  has  a 

medium  strength  and  a medium  bonding 

strength.  The  drying 

shrinkage 

is  medium  and  at  cone  9 the  total  shrinkage  is  medium  high.  The  clay 

attains  a 

fairly  low  degree  of  porosity  at  cone 

6 and  is  not 

overburned  at  cone  15. 

It  is  a refractory  clay. 

Suggested  uses : Stoneware,  architectural  terra  cotta,  sanitary  ware,  refractories, 
face  brick. 


Sample  No.  C82 

(West  pit  of  the  Utica  Firebrick  and  Clay  Company,  near  Utica) 

This  sample  was  a mixture  of  a light  colored  material,  which  was  very  hard, 
and  a soft  yellow  mass.  When  tempered  with  water  it  developed  a very  good  plas- 
ticity and  could  be  squeezed  through  a die  satisfactorily. 


I A SALLE  COUNTY 


127 


Water  of  plasticity per  cent  32 

Shrinkage  water  per  cent  16.9 

Pore  water  per  cent  15.1 

Modulus  of  rupture lbs.  per  sq.  in.  484.8 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  185.2 

Slaking  test,  average min.  9 


Screen  test : — 


Mesh 

Residue 

Character  of  residue 

Per  cent 

10 

7.8 

Sand, 

colored 

rock  fragments 

14 

3.5 

Sand, 

colored 

rock  fragments 

20 

3.5 

Sand, 

colored 

rock  fragments 

35 

1.3 

Sand, 

colored 

rock  fragments, 

and 

coal 

48 

Sand, 

colored 

rock  fragments, 

and 

coal 

65 

1.0 

Sand, 

colored 

rock  fragments, 

and 

coal 

100 

T race 

150 

Trace 

200 

Drying  shrinkage : — 

Per  cent 

Linear  6.8 

Burning  test : — 


Total 

Cone 

Porosity 
Per  cent 

Color 

shrinkage 
Per  cent 

Remarks 

02 

33.7 

Reddish  cream  

1.8 

1 

3.9 

Dark  grav  

12.7 

Very  brittle 

3 

2.2 

Dark  gray  

13.6 

Very  brittle 

5 

1.0 

Dark  brown 

12.5 

Bloated.  Sample  heated 
above  this  cone  was 

melted. 

Fusion  test: — Complete  fusion  at  cone  26.  Cone  shows  vesicular  structure,  but  not 
very  decided. 


Summary 

The  strength  of  the  clay  is  medium  high.  Its  bonding  strength  is  medium  low. 
The  drying  shrinkage  is  medium.  Total  shrinkage  at  cone  5 is  medium  high.  It 
appears  bloated  as  though  overburned  at  cone  5.  The  clay  is  non-refractory. 

Suggested  uses : Common  brick  and  tile. 

Sample  No.  97 

(M.  J.  Gorman  and  Company’s  pit;  1^  miles  south  of  Utica) 

The  following  tests  relate  to  the  sample  collected  by  Mr.  Culver. 

The  material  is  of  a medium  hard  shaly  nature.  With  it  is  mixed  a softer  por- 
tion. The  color  is  dark  gray  and  brown.  A good  plasticity  may  be  developed.  When 
forced  through  a die,  the  clay  flows  rather  badly. 


Water  of  plasticity  per  cent  35.6 

Shrinkage  water  per  cent  22.9 

Pore  water  per  cent  12.5 

Modulus  of  rupture lbs.  per  sq.  in.  565 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  201 

Slaking  test,  average min.  60 


128 


ILLINOIS  FIRE  CLAYS 


Screen  test: — 

Mesh 

20 

40 

60 

80 

120 

150 

200 

Drying  shrinkage : — 


Linear ; dry  length  

Linear : wet  length  

Drying  conduct : — Shows  tendency  to  warp. 
Burning  test : — 


Cone  Porosity  Color 

Per  cent 

08  30  Salmon  

06  27  Buff  

04  24  Cream  

02  23  Buff  

1 22  Buff  

2 16  Stoneware  

4 9.5  Gray  

7 5.6  Gray  

9 6.5  Gray 

10  4.4  Gray  with  brown  specks 

Fusion  test: — It  fused  at  cone  28. 


Residue 
Per  cent 
. 0.3 

17.3 
17.6 
6.0 

. 0.8 
1.8 
, 4.0 


Per  cent 
..  10.5 

..  9 


Burning 
shrinkage 
Per  cent 

..  1.6 
..  2.2 
..  3.1 
..  4.0 
..  4.6 
..  5.4 
..  5.7 
..  5.2 
. . 5.5 
..  5.3 


Summary 

The  strength  of  the  clay  is  medium  high.  Its  bonding  strength  is  medium. 
The  total  percentage  of  residue  on  the  screens  is  high.  The  drying  shrinkage  is 
medium  high  at  cone  9.  The  total  shrinkage  is  high.  The  vitrification  proceeds 
slowly  and  is  incomplete  at  cone  10.  It  is  a refractory  clay. 

Suggested  uses : Refractories,  face  brick. 

Sample  No.  100 

(M.  J.  Gorman  and  Company’s  pit;  \l/2  miles  south  of  Utica) 

Resampled  by  Mr.  Culver. 

The  clay  is  a very  hard  gray  colored  material.  Its  conduct  when  forced  through 


a die  is  good. 

Water  of  plasticity per  cent  24.6 

Shrinkage  water  per  cent  13.8 

Pore  water  per  cent  10.8 

Modulus  of  rupture lbs.  per  sq.  in.  475 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  222 

Slaking  test,  resample min.  40 


LA  SALLE  COUNTY 


129 


Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 

20 0.2  Fragments  of  rock  and 

pyrites 

40 0.06  Sand  and  pyrites 

60 3.5  Sand,  particles  of  clay 

and  pyrites 

80 2.1  

120 14.1  Particles  of  clay 

150 3.4  Particles  of  clay 

200 6.5  Particles  of  clay 


The  sample  did  not  slake  completely. 

Drying  shrinkage: — Linear;  wet  length per  cent  7.3 

Burning  test : — 

Burning- 


Cone 

08 

Porosity 
Per  cent 

24 

Color 

Lisrht  errav  

shrinkage 
Per  cent 

2.1 

06 

23 

Buff  and  cream  

2.5 

04 

20 

Dark  cream  

3.3 

02 

18 

Dark  cream 

4.0 

1 

16 

Dark  cream  

4.4 

3 

12 

Gray  

5.0 

5 

8 

Gray  with  iron  speckles  

5.5 

7 

6 

5.5 

9 

6 

5.5 

11 

7 

Brown  

5.7 

Fusion  test: — It  deformed  at  cone  31. 


Summary 

The  strength  of  the  clay  is  medium  high.  Its  bonding  strength  is  medium.  The 
amount  of  screen  residues  is  high.  The  drying  shrinkage  is  medium.  The  total 
shrinkage  at  cone  9 is  medium  high.  Vitrification  is  incomplete  at  cone  11.  It  is  a 
refractory  clay. 

Suggested  uses:  Refractories,  face  brick.  The  slow  slaking  properties  may 
limit  its  usefulness  for  terra  cotta,  stoneware,  and  sanitary  ware. 

Sample  No.  98 

(Side  of  gully  near  M.  J.  Gorman  and  Company’s  pit,  near  Utica) 

This  report  relates  to  sample  obtained  by  Mr.  Culver. 

This  is  a soft  clay,  yellow  in  color  and  marked  with  brown  spots.  When  tem- 


pered with  water,  it  has  good  plasticity. 

Water  of  plasticity per  cent  28 

Shrinkage  water  per  cent  12.7 

Pore  water  per  cent  15.3 

Modulus  of  rupture lbs.  per  sq.  in.  246 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  149 

Slaking  test,  average min.  65 


130 


ILLINOIS  FIRE  CLAYS 


Screen  test : — 


Mesh 

Residue 
Per  cent 

Character  of  residue 

20 

...  42 

Chert  and  sandstone  fragments 

40. . .,  

1.0 

60 

2.8 

80 

5.3 

White  and  yellow  sand 

120 

2.2 

White  and  yellow  sand  with  some 

mica 

150 

2.00 

White  and  yellow  sand  with  some 

mica 

200 

4.8 

White  and  yellow  sand  with  some 

mica 

Drying  shrinkage: — Linear;  wet  length per  cent  6.2 


Burning  test: — 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Per  cent 

Per  cent 

08 

36 

Brownish  red  

1.7 

06 

34 

Brownish  red  

2 ? 

04 

32 

Brownish  red  

3.4 

02 

31 

Brownish  red  

3.8 

1 

30 

Brownish  red  

4.3 

3 

28 

Chocolate  

5.0 

5 

22 

Bluish  black  

6.2 

7 

19 

Bluish  black 

6.8 

9 

17 

Bluish  black 

7.6 

Fusion  test: — It  deforms  at  cone  29. 

Summary 

The  clay  has  a medium  strength,  a medium  low  bonding  strength,  and  a medium 
drying  shrinkage.  It  contains  a considerable  percentage  residue  material  too  coarse 
to  pass  the  screen  test.  The  total  shrinkage  at  cone  9 is  medium  high.  The  clay  is 
quite  open  burning.  The  very  dark  color  of  the  samples  carried  to  cone  5 and  beyond 
suggests  the  possibility  of  reduction  during  burning.  It  is  refractory. 

Suggested  uses  : Face  brick.  The  dark  color  of  the  burned  clay  and  its  burning 
conduct  suggest  the  possibility  of  the  iron  content  being  abnormally  high  for  a re- 
fractory material,  even  though  the  fusion  test  was  satisfactory. 

Sample  No.  93 

(Illinois  Clay  Products  Company’s  mine  at  Deer  Park) 

This  is  a dark  gray  colored  clay  which  is  a semi-flint  in  its  character.  It  appears 


to  contain  a notable  amount  of  pyrites. 

Water  of  plasticity Per  cent  25 

Shrinkage  water  per  cent  15.9 

Pore  water  per  cent  9.1 

Modulus  of  rupture lbs.  per  sq.  in.  554.7 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  302.5 

Slaking  test,  average min.  \0l/> 

Drying  shrinkage  : — 

Per  cent 

Linear ; wet  length  7.2 

Linear ; dry  length  7.8 

Volume  32.6 


LA  SALLE  COUNTY 


131 


Burning  test : — 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

2 

72 

Grayish  white  

6.0 

Nearly  vitreous 

3 

3.3 

Gray  

6.3 

Nearly  vitreous  frac- 

ture 

6 

3.0 

Gray  

6.6 

Nearly  vitreous 

8 

2.2 

Gray  

5.5 

Some  fine  iron  spots 

12 

11.8? 

Bluestoned  

2.6 

13 

7.3 

Buff  ; slagged  spots  ; 

blue  core.  3.2 

Buff  exterior,  blue  core, 

numerous  iron  spots 

15 

4.6 

Dark  terra  cotta  flash  outside ; 

gray  inside 

4.0 

Large  iron  spots  over- 

burned 

Fusion  test  : — It  deformed  at  cone  29. 

Summary 

The  strength  of  the  clay  is  medium  high  and  its  bonding  strength  is  medium. 
The  drying  shrinkage  is  medium.  The  total  shrinkage  at  cone  8 is  medium  high. 
It  is  practically  non-porous  at  cone  8 and  is  slightly  overburned  at  cone  13.  It  is  a 
refractory  clay. 

Suggested  uses  : Refractories,  especially  those  requiring  a clay  having  a good 
strength  and  burning  to  a dense  structure.  Facebrick.  Its  slow  slaking  property 
when  mixed  with  water  is  rather  unfavorable  for  its  use  for  stoneware  and  terra  cotta. 

Sample  No.  96 

(Illinois  Clay  Products  Company’s  mine  at  Deer  Park) 

The  sample  was  a hard,  dark  gray  colored  material  of  medium  plasticity. 


Water  of  plasticity  

19 

Shrinkage  water 

10 

Pore  water  

0 

Modulus  of  rupture  

277 

With  50%  standard  sand — Modulus  of  rupture  . . 

107.3 

Slaking  test,  average  

Screen  test: — Too  hard  t,o  slake. 

7 

Drying  shrinkage : — 

Per 

cent 

Linear ; dry  length  

5.8 

Linear ; wet  length  

5.5 

Volume  

20.5 

Burning  test : — 

Burning 

Cone  Porosity  Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02  18  White  

3.9 

2 17  Light  cream 

3 14  Light  cream 

6 12  Light  cream 

9 7 Cream  

. . . . 4.4 

Earthy  fracture 

. . . . 6 

Earthy  fracture 
Granular 

....  6.1 

12  3.0  Bluestoned ; 

uniform  gray. . 

....  7 

Earthy  fracture 

13  2.4  Bluestoned ; 

uniform  gray  . , 

. . . . 6.8 

Earthy  fracture 

15  2.4  Bluestoned ; 

uniform  gray  . 

. . . . 7.0 

132 


ILLINOIS  FIRE  CLAYS 


Fusion  test: — It  fused  about  cone  31. 


Summary 

The  strength  of  the  clay  is  medium  and  its  bonding  strength  is  medium  low. 
The  drying  shrinkage  is  medium.  At  cone  9 the  total  shrinkage  is  medium.  Vitri- 
fication is  nearly  complete  at  cone  12  and  there  is  no  sign  of  overburning  at  cone  15. 
It  is  refractory. 

Suggested  uses : Refractories  and  face  brick.  Its  slow  slaking  is  rather  unsatis- 
factory for  stoneware  and  architectural  terra  cotta. 


Sample  No.  90 


(Lowell  Stoneware  Company’s  pit ; at  Lowell) 

This  is  a hard  dark  colored,  i.  e.,  gray  clay  which  becomes  very  plastic  when 
tempered  with  water.  Its  conduct  when  flowing  through  a die  is  very  good. 


Water  of  plasticity per  cent  20.8 

Shrinkage  water  per  cent  8.5 

Pore  water  per  cent  12.2 

Modulus  of  rupture lbs.  per  sq.  in.  420 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  290 

Slaking  test,  average  min.  9 

Screen  test : — Clay  was  too  hard  to  slake. 

Drying  shrinkage : — 

Per  cent 

Linear;  dry  length  6.8 

Linear;  wet  length  6.2 

Burning  test: — 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

18 

White  

4.1 

3 

14 

Light  cream  . . 

5.0 

Earthy  fracture 

6 

12 

Light  cream  . . 

Earthy  fracture 

9 

9.5 

Cream  

5.7 

12 

5.0 

Darker  cream 

7.0 

Granular  but  vitreous 

fracture 

15 

2.0 

Tan  exterior; 

bluestoned  badly.  7.6 

Fusion  test : — Deformation  at  cone 

30/31. 

Summary 

The  strength  of  the  clay  is  medium  high  and  its  bonding  strength  is  medium. 
Because  of  its  hardness,  the  clay  could  not  be  slaked  properly  for  the  screen  tests. 
The  drying  shrinkage  is  medium.  The  total  shrinkage  at  cone  9 is  medium.  Vitri- 
fication is  practically  complete  at  cone  15.  It  is  a refractory  clay. 

Suggested  uses:  Refractories,  especially  if  good  bonding  power  is  desired.  Its 
slow  slaking  property  is  a disadvantage  for  stoneware  and  architectural  terra  cotta, 
although  otherwise  it  seems  adapted  to  these  uses. 


Sample  No.  89 
(Near  river  bank  at  Lowell) 

This  report  relates  to  a resampling  of  the  deposit  by  Mr.  Culver.  This  hard 
clay  is  of  a gray  color  and  it  has  a low  degree  of  plasticity.  The  conduct  of  the 
plastic  body  when  forced  through  a die  is  only  fair. 


LA  SALLE  COUNTY 


133 


Water  of  plasticity per  cent 

Shrinkage  water per  cent 

Pore  water  per  cent 

Modulus  of  rupture  lbs.  per  sq.  in. 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in. 

Slaking  test,  average min. 

Screen  test : — 


18 

6.6 

11.3 

179 

137.6 

12 


Mesh 

Residue 

Character  of  residue 

Per  cent 

20... 

4.5 

Particles  of  coal, 

rock  and  pyrites 

40... 

6.8 

Particles  of  coal, 

rock  and  pyrites 

60... 

2.3 

Particles  of  coal, 

rock  and  pyrites, 

some  mica 

80... 

1.1 

Particles  of  clay 

120... 

0.9 

Particles  of  clay 

150... 

2.0 

Particles  of  clay 

200... 

9.4 

Particles  of  clay 

Drying  shrinkage 

-Linear  

Burning  test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

08 

30 

White  

+.4 

06 

27 

Cream 

...+0.3 

04 

28 

Cream  

....-0.1  

02 

1 

3 

5 

7 

9 

11 


28 

27 

25 

19 

19 

17 

12 


Cream  0.26 

Cream  0.3 

Cream  1.0 

Cream  with  black  spots 2.5 

Cream  with  black  specks 2.2 

Black  specks  2.0 

Black  specks  2.5 


Appears  overburned 


Fusion  test: — Fused  completely  at  cone  26. 


Summary 

The  strength  of  the  unburned  clay  is  medium  low.  Its  bonding  strength  is 
medium  low.  The  amount  of  residues  on  the  sieves  is  high.  The  total  shrinkage 
at  cone  9 is  medium  low.  The  vitrification  is  still  quite  incomplete  at  cone  11,  al- 
though it  has  the  appearance  of  having  been  overburned.  It  is  a non-refractory  clay. 

Suggested  uses : Stoneware,  although  the  hardness  and  slow-slaking  properties 
together  with  the  low  strength  may  be  quite  disadvantageous ; face-brick. 


Sample  No.  95 

(Herrick  Clay  Manufacturing  Company;  1 mile  east  of  Twin  Bluffs) 

This  sample  appears  to  be  a mixture  of  clay  and  quartzite  lumps  and  grains. 
It  is  a grayish  or  dark  color. 

Modulus  of  rupture  lbs.  per  sq.  in.  157 

Slaking  test,  average  min.  6 


J 34 


ILLINOIS  FIRE  CLAYS 


Screen  test : — 


Mesh  Residue  Character  of  residue 

Per  cent 

20 3.5' 

40 1.8 

60 13.9  C Quartz  sand  and  pyrites 

120 23.3 

200 2.6 

Fusion  test Deforms  at  cone  27. 


Summary 

The  strength  test  is  medium  low.  The  percentage  of  residues  on  the  screens 
is  high.  It  is  refractory. 


Sample  No.  94 

(National  Fireproofing  Company’s  pit  at  Twin  Bluffs) 

The  sample  is  a dark  gray,  hard  clay  which  contains  some  sandy  material.  When 
tempered  with  water  a medium  degree  of  plasticity  may  be  developed.  It  does  not 
flow  readily  through  the  die. 

Water  of  plasticity  

Shrinkage  water  

Pore  water  

Modulus  of  rupture 

Slaking  test,  average  

Screen  test : — Sample  does  not  slake. 

Drying  shrinkage : — 


per  cent  16.9 

per  cent  7.6 

per  cent  9.2 

lbs.  per  sq.  in.  140.6 
min.  8^2 


Linear : dry  length 
Linear ; wet  length 

Volume  

Burning  test : — 


Per  cent 
..  4.0 

..  3.9 
..  15.9 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

24.7 

Gray 

1 

1 

25.3 

Grayish  white  . . 

...  1.0 1 

3 

24.6 

Cream  

...  1.5 

! 

5 

21.9 

Light  brown  . . . . 

T 

Specked  with  iron 

7 

22.1 

Light  brown  . . . . 

. . . 2.0 

9 

22 

Dark  brown 

. . . 2.0 

12 

19 

Terra  cotta  

. . . 2.0 

Color  may  be  due  to 

flashing 

13 

16 

Red  brown  with 

black  spots 

on 

interior 

. . . 3.0 

15 

11 

Bluestoned,  gray 

black 

. . . 5.0 

Oxidation  conduct : — Material  seems  to  flash  very  readily. 
Fusion  test: — It  deforms  at  cone  31. 


Summary 

The  strength  of  the  clay  is  medium  low. 
At  cone  9 the  total  shrinkage  is  medium  low. 


Its  drying  shrinkage  is  medium  low. 
The  clay  is  quite  open  burning,  vitri- 


LA  SALLE  COUNTY 


135 


fication  being  incomplete  at  cone  15.  It  is  a refractory  clay. 

Suggested  uses : The  rather  poor  plasticity  may  render  it  difficult  to  form  this 
clay  readily;  otherwise  it  is  adapted  to  use  for  face  brick.  Although  the  fusion 
test  indicates  a material  of  refractory  nature,  yet  the  presence  of  numerous  iron 
spots  as  indicated  at  the  lower  cones  is  not  very  satisfactory. 


Sample  No.  91 

(National  Fireproofing  Company’s  pit;  2 miles  east  of  Ottawa) 

This  is  a hard  clay  of  a dark  gray  color  which  contains  a notable  amount  of 
pyrites.  It  is  fairly  plastic. 

Water  of  plasticity per  cent  17.3 

Shrinkage  water  per  cent  9.1 

Pore  water  per  cent  8.2 

Modulus  of  rupture lbs.  per  sq.  in.  309.5 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  236.7 

Slaking  test,  average  min.  9 

Screen  test : — ■ 

Mesh  Residue  Character  of 

Per  cent  residue 


Trace 

0.3 

2.3 

1.1 

2.1 

2.4 


Pyrite  and  sand 


20 

40 

60 

80 

120 

200 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  6.8 

Linear;  wet  length  6.3 

Volume  18.9 

Burning  test 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04 

24.8 

White  

....  2.6 

Fine  specks  of  iron  oxide 

02 

22.4 

White  

. . . . 3.5 

Fine  specks  of  iron  oxide 

2 

18.5 

Grayish  white  

. . . . 4.8 

Granular 

5 

16.5 

Grayish  white  

. . . . 5.4 

Granular 

9 

14.0 

Grayish  white  

. . . . 5.6 

Numerous  fine  iron  spots 

13 

7.9 

Grayish  white  

. . . . 7.0 

14 

6.3 

Brown  red ; bluestoned  . 

. . . . 5.3 

Iron  ^pots,  slagged 

15 

16.3 

Brown  red  ; bluestoned  . 

. . . . 4.8 

Iron  spots,  slagged 

Fusion 

test: — Fused  completely  at  cone  27. 

Summary 

The  strength  of  the  clay  is  medium  and  its  bonding  strength  is  medium.  The 
percentage  of  residues  left  on  the  sieves  is  moderate.  The  drying  shrinkage  is 
medium  and  the  total  shrinkage  at  cone  9 is  medium.  Vitrification  is  incomplete  at 
cone  14  and  apparently  the  clay  is  overburned  at  cone  15.  It  is  non-refractory. 

Suggested  uses:  Stoneware,  architectural  terra  cotta  and  sanitary  ware  (the 
presence  of  pyrites  may  make  this  use  impossible),  face  Ibrick. 


136 


ILLINOIS  FIRE  CLAYS 


Sample  No.  92 

(National  Fireproofing  Company’s  pit;  2 miles  east  of  Ottawa) 


This  is  a very  hard  clay  of  a light  gray  color. 
It  flows  readily  through  a die. 

Water  of  plasticity 

Shrinkage  water  

Pore  water 

Modulus  of  rupture 

Slaking  test,  average  

Drying  shrinkage : — 


It  has  only  a medium  plasticity. 

per  cent  17 

Per  cent  6.9 

per  cent  10.1 

lbs.  per  sq.  in.  201 

min.  5 


Per  cent 

Linear ; dry  length  4.7 

Volume  14 


Burning  test: — 


Cone 

01 

Porosity  Color 

Per  cent 

17.8  White  

Burning 
shrinkage 
Per  cent 
4.7 

Remarks 

2 

17 

Light  cream 

4.9 

Earthy  fracture 

3 

13 

Light  cream 

6.0 

Earthy  fracture 

6 

12 

Light  cream 

6.4 

Earthy  fracture 

9 

8 

Light  cream 

6.2 

Earthy  fracture 

12 

4.7 

Darker  light  buff 

6.9 

Very  fine  iron  spots 

evenly  distributed 

15 

6.1 

Light  buff ; bluestoned  . . . 

7.1 

Fusion  test: — It  deformed  at  cone  29. 

Summary 

The  strength  of  the  clay  is  medium.  Its  drying  shrinkage  is  medium  low.  The 
total  shrinkage  at  cone  9 is  medium.  It  still  has  an  appreciable  porosity  at  cone  12  and 
apparently  is  slightly  overburned  at  cone  15.  It  is  a refractory  clay. 

Suggested  uses : Refractories,  stoneware,  architectural  terra  cotta. 

Sample  No.  101 

(Chicago  Retort  and  Firebrick  Company’s  pit,  northeast  of  Ottawa) 

This  is  a dark  gray  colored,  very  hard  clay,  which  develops  a fair  plasticity 
when  tempered  with  water.  It  flows  only  fairly  well  through  a die. 


Water  of  plasticity  per  cent  20.0 

Shrinkage  water  per  cent  11.5 

Pore  water  per  cent  8.5 

Modulus  of  rupture,  maximum  lbs.  per  sq.  in.  532 

Modulus  of  rupture,  average lbs.  per  sq.  in.  335 

With  50%  standard  sand — Modulus  of  rupture : — 14  of  20  pieces  gave  an 

average  (not  including  values  of  292.5  and  296.0) lbs.  per  sq.  in.  177 

Slaking  test,  average rnin.  7J4 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  7.0 

Linear;  wet  length 6.5 

Volume  23.5 


LA  SALLE  COUNTY 


137 


Burning  test : — 

Burning 


Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

19 

Cream  

. ...  3.6 

2 

17 

Cream  

. . . . 4.0 

Earthy  fracture 

4 

Cream  

. . . . 4.4 

Earthy  fracture 

6 

15 

Darker  cream  

. . . . 4.2 

Earthy  fracture 

9 

13 

Cream  

. . . . 4.4 

Earthy  fracture 

12 

11 

Light  terra  cotta  : flashed  . . 

....  4.1 

Many  fine  iron  spots 

13 

12 

Light  terra  cotta;  flashed.. 

. . . . 4.6 

Many  fine  iron  spots, 

slagged 

15 

13 

Buff  

. . . . 5.3 

Golden  buff,  numerous 

iron  spots 

Fusion 

test It  deforms  at  cone  29. 

Summary 

The  tests  of  the  clay  showed  it  to  have  medium  strength,  but  it  should  be  noted 
that  a single  test  piece  gave  a much  higher  value.  The  bonding  test  also  gave  two 
values,  considerably  higher  than  the  average  of  a large  number  of  pieces.  The  drying 
shrinkage  is  medium.  The  total  shrinkage  at  cone  9 is  medium.  Vitrification  is  incom- 
plete at  cone  12,  at  which  temperature  it  is  still  quite  open.  Apparently  slight  over- 
burning occurs  above  this  point.  The  clay  is  refractory. 

Suggested  uses : Face  brick,  stoneware,  architectural  terra  cotta,  sanitary  ware, 
refractories. 


Sample  No.  99 

(Dayton  Clay  Works ; Yz  mile  south  of  Dayton) 


The  clay  is  of  a dark  gray  color.  It  is  quite  sandy  (see  screen  test),  and  the 
plasticity  is  low.  It  flows  poorly  through  a die. 

Water  of  plasticity  per  cent  15.9 

Shrinkage  water  per  cent  5.1 

Pore  water  per  cent  10.8 

Modulus  of  rupture lbs.  per  sq.  in.  215 


With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in. 

Slaking  test,  resample  min. 

Screen  test : — 

Mesh  Residue 

Per  cent 

20 4.9 


107 

22]/2 


40. 

60. 

80. 

120. 

200. 


Character  of 
residue 

Pyrites  and  carbona- 
ceous matter 

0.3  Pyrites  and  quartz  sand 
5.8  White  quartz  sand 

3.7  Quartz  sand 

8.4  Quartz  sand 

4.5  Darker  colored  sand 


Drying  shrinkage : — 

Per  cent 


Linear ; dry  length  4.9 

Linear ; wet  length  4.7 

Volume  9 


138 


JLUNOIS  FIRE  CLAYS 


Burning  test : — 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

08 

30 

Light  gray  white  

2.0 

06 

30 

Light  gray  white  

2.0 

04 

30 

Light  gray  white  

2.0 

02 

29 

Light  gray  white  

4.1 

1 

25 

Light  gray  white 

6.2 

3 

22 

Licht  orrav  white  

9.3 

5 

Light  gray  white;  iron  specks..  8.3 

6 

23 

Slightly  darker 

7 

Slightly  darker 

6.2 

9 

19 

Slightly  darker 

12 

16 

Terracotta;  flashed 

Numerous  iron  spots 

15 

21 

Terracotta;  flashed 

Many  large  iron  spots 

Fusion  test: — It  fused  at  cone  30. 

Summary 

The 

clay  has 

a medium  strength,  and  a 

medium  low 

bonding  strength.  The 

amount  of 

screen  residues  is  high.  The  drying 

shrinkage  is  medium  low.  The  mini- 

mum  porosity  was  reached  at  cone  12  and  it  appeared  to  overburn  at  cone  15. 
fusion  test  indicates  a refractory  clay. 

Suggested  uses : Face  brick.  Certain  types  of  refractories. 


The 


Sample  No.  102 
(Resampled  by  H.  E.  Culver) 

(Dayton  Clay  Works ; y2  mile  south  of  Dayton) 


This  is  a hard  clay  which  is  dark  gray,  nearly  black  in  color.  When  tempered 
with  water,  it  becomes  very  plastic  and  flows  through  a die  satisfactorily. 


Water  of  plasticity per  cent  33 

Shrinkage  water per  cent  12 

Pore  water per  cent  21 

Modulus  of  rupture lbs.  per  sq.  in.  297 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  22 3 

Slaking  test,  average  min.  13 


Screen  test : — 

Mesh 

(Sample  slaked  badly.) 

20 

40 

60 

80 

120 

150 

200 


Residue 
Per  cent 
. 0.8 
. 0.3 

. 1.9 

. 0.4 

. 1.0 
. 0.6 
. 0.9 


Character  of 
residue 


Sand 


Clay  particles 


Drying  shrinkage: — Linear;  wet  length  per  cent  6.0 


I. A SALLE  COUNTY 


139 


Burning  test 

Burning 

Cone  Porosity  Color  shrinkage 

Per  cent  Per  cent 

08  29  Salmon  3.0 

06  23  Brownish  red  4.4 

04  15  Darker 6.3 

02  12  Chocolate  7.6 

1 7 Gray 9.2 

3 1.2  Greenish  black 9.4 

5 Overburned 


Fusion  test: — Completely  fused  at  cone  27.  Vesicular. 

Summary 

The  clay  has  a medium  strength  and  a medium  bonding  strength.  It  slakes 
rather  poorly  and  leaves  a moderate  amount  of  residues  upon  the  screens.  The 
drying  shrinkage  is  medium.  The  clay  has  a short  heat  range.  It  reaches  a minimum 
porosity  at  cone  3 and  is  overburned  at  cone  5.  It  is  non-refractory. 

Suggested  uses : Brick  and  tile. 


Sample  No.  129 
(Resampled  by  Mr.  Culver) 

(Chicago  Firebrick  Company’s  shaft;  2 miles  east  of  Marseilles) 


This  clay  has  a dark  gray  color.  It  is  very  hard.  When  tempered  with  water, 
it  has  good  plasticity.  Its  conduct  when  squeezed  through  a die  is  fair. 


Water  of  plasticity  

Shrinkage  water  

Pore  water  

Modulus  of  rupture,  maximum  

Modulus  of  rupture,  average 

With  50%  standard  sand — Modulus  of  rupture  . . 

Slaking  test,  2nd  sample  

Screen  test : — 

Mesh 

Residue 

Character  of 

Per  cent 

residue 

20 

. ...  1.2 

Quartz,  coal,  pyrites 

40 

. . . . 0.4 

60 

0.8 

80 

. . . . 1.3 

Particles  of  hard  clay 

120 

. . . . 0.4 

Particles  of  hard  clay 

150 

. . . . 0.3 

Particles  of  hard  clay 

200 

....  1.27 

Particles  of  hard  clay 

Drying  shrinkage : — 

Per  cent 

Linear ; dry  length  

12.5 

Linear ; wet  length  

10.0 

140 


ILLINOIS  FIKE  CLAYS 


Burning  test: — 


Cone 

Porosity 

Color 

Burning 

shrinkage 

08 

Per  cent 
22 

Cream  

Per  cent 

1.5 

06 

20 

Cream  

2.1 

04 

13 

Grayish  

3.0 

02 

12 

Grayish  

4.0 

1 

7 

Grayish  

42 

3 

8 

Grayish  

4.4 

4 Overburned  Iron  spots 

Fusion  test: — It  deforms  at  cone  27/28. 

Summary 

The  strength  of  this  clay  as  determined  by  taking  the  average  of  nineteen  of 
twenty-one  test  pieces  is  medium  high.  It  should  be  noted  that  the  maximum  strength 
test  of  900  pounds  per  square  inch  was  obtained  with  four  test  pieces.  The  bonding 
test  was  medium.  The  amount  of  residues  left  upon  the  screens  was  moderate.  The 
drying  shrinkage  was  medium  high  and  the  total  shrinkage  at  cone  1 was  high.  The 
sample  appeared  to  be  overburned  at  cone  4.  The  fusion  test  indicates  a refractory 
clay. 


Sample  No.  130-a 

(Streator  Clay  Manufacturing  Company’s  shaft;  2 miles  south  of  Streator) 

This  is  a dark  colored,  very  hard  clay,  which  contains  much  pyrite.  Its  slaking 
time  averages  6l/i  minutes.  It  is  completely  fused  at  cone  25. 

Sample  No.  130-b 

(Streator  Clay  Manufacturing  Company’s  shaft;  2 miles  south  of  Streator) 

This  is  a dark  colored,  i.  e.,  grayish,  very  hard  clay.  The  average  time  of  the 
slaking  test  was  nineteen  minutes.  It  is  completely  fused  at  cone  25. 

Sample  No.  131 

(Spring  Lake  Coal  Company’s  shaft  at  Kangley) 

This  is  a hard,  greenish-gray  colored  clay,  which  is  stained  with  iron  oxide.  It 
has  a conchoidal  fracture.  When  tempered  with  water,  a medium  plasticity  may  be 
developed.  Its  conduct  when  forced  through  a die  is  satisfactory.  The  occurrence 


of  gypsum  crystals  in  the  clay  was  noted. 

Water  of  plasticity per  cent  29.7 

Shrinkage  water  per  cent  13.3 

Pore  water per  cent  16.4 

Modulus  of  rupture  lbs.  per  sq.  in.  361.8 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  192.6 

Slaking  test,  average  min.  15 

Drying  shrinkage : — 

Per  cent 

Linear  5.7 

Volume  20.0 


LA  SALLE  COUNTY 


141 


Screen  test : — 


Mesh  Residue  Character  of 

Per  cent  residue 

10 0.9  ' 

14 1.0 

20 1.1 

35 2.6 

48  1.18  - Particles  of  shale,  pyrite, 

65 1.0  and  coal 

100 0.8 

150 0.65 

200 0.50 


Burning  test : — 

Cone 

Porosity 

Color 

Total 

shrinkage 

Remarks 

04 

Per  cent 
10.3 

Terra  cotta  

Per  cent 
13.9 

Scummed  by  efflorescent  salts 

01 

1.75 

Terra  cotta  

15.3 

Vitreous  glassy  fracture 

3 

0.9 

Reddish  brown  . . . 

15.3 

Vitreous  glassy  fracture 

5 

4.8 

Brown  

Overburned,  bloated 

7 

11.8 

Brown  

Overburned,  bloated 

Soluble  salts : — Salts  appear  on  the  pieces  after  burning. 
Fusion  test*: — It  fused  at  cone  25. 


Summary 

The  strength  of  the  clay  is  medium.  Its  bonding  strength  is  medium  low.  The 
amount  of  coarse  particles  is  moderate  and  the  fractions  are  quite  evenly  distributed. 
The  total  shrinkage  at  cone  3 is  high.  The  clay  vitrifies  rapidly  at  a low  temperature 
and  is  overburned  at  cone  5,  thus  having  a very  limited  heat  range.  It  is  non- 
refractory. 

Suggested  uses  : Common  brick. 


GRUNDY  COUNTY 

An  exceptional  thickness  of  clay  is  found  in  the  depression  formerly 
occupied  by  Goose  Lake.  Lenses  of  this  clay  are  of  a semi-flinty  nature 
and  thin  layers  of  coal  are  interbedded  with  it.  This  coal  varies  in  thick- 
ness, and  at  the  west  end  will  total  6 or  7 feet.  The  total  thickness  of  the 
clay  is  reported  to  vary  from  30  to  40  feet  and  the  overburden  over  the 
200  acre  deposit  ranges  from  practically  nothing  to  6 or  8 feet  with  an  aver- 
age of  about  3 feet.  A drilling  30  feet  deep  did  not  reach  the  bottom  of 
the  clay.  “Islands”  of  rock  are  found  in  the  clay  and  suggest  its  accumula- 
tion in  solution  basins  in  the  crystalline  Richmond  limestone  which  out- 
crops at  the  north ; at  least  these  basins  were  in  some  way  partly  separated 
from  the  main  “Coal  Measures”  sea  at  the  south.  Fig.  56  is  a view  of  the 
clay  pit  at  the  west  end  of  the  Goose  Lake  area. 

A face  exposed  in  the  bank  of  a small  test  pit  is  as  follows : 


142 


ILLINOIS  FIRE  CLAYS 


Fig.  56.  View  of  the  clay  pit  at  the  west  end  of  the  Goose  Lake  area  in  Grundy  County. 
Section  of  upper  part  of  Goose  Lake  clay 

Thickness 
Ft.  In. 


5.  Peaty  soil  and  peat  8 to  10 

4.  Sandstone,  local  thin  lenses  0 to  3 

3.  Fireclay,  flint  or  semi-flint,  drab,  stained  by  iron  and  showing 

colorings  of  carbon  (Sample  No.  133) 1 

2.  Shale,  stained  black  by  carbon  6 

1.  Clay,  drab  gray  with  yellow  stains  of  iron  oxide  (Sample  No.  134)  3 6 


The  upper  “flint”  or  “semi-flint”  is  underlain  by  a thin  coal  which  is  in 
turn  above  a plastic  clay  of  lower  refractory  value. 

An  additional  sample,  known  as  No.  X,  which  was  obtained  from  a pit 
on  the  Anderson  farm  in  Goose  Lake  Township,  Grundy  County,  was  col- 
lected and  shipped  to  the  Survey  by  D.  C.  Haeger.  It  is  known  as  No.  1 
fire  clay,  according  to  Mr.  Haeger.  The  clay  lies  in  a bed  5 feet  in  thick- 
ness and  is  covered  by  20  to  24  feet  of  soft  stone,  30  to  36  feet  of  sandstone, 
and  16  inches  of  black  soil. 

Results  of  tests  on  sample  No.  X are  given  on  page  144. 

RESULTS  OF  TESTS 

GRUNDY  COUNTY 

Sample  No.  133 

(Clay  pit  at  the  west  end  of  the  Goose  Lake  area) 

This  is  a drab  colored,  flinty  clay,  stained  with  iron.  When  ground  and  tem- 
pered with  water,  it  develops  a medium  plasticity. 


GRUNDY  COUNTY 


143 


Water  of  plasticity 

Shrinkage  water  

Pore  water  

With  50%  standard  sand — Modulus  of  rupture 

Slaking  test,  average  

Screen  test : — 

Mesh 

40 

60 

80 

120 

200 

Drying  shrinkage : — 

Linear  ; dry  length 

Linear ; wet  length  

Volume  


per  cent  18.2 

per  cent  8.6 

per  cent  9.6 

lbs.  per  sq.  in.  59.6 
min.  3 


Residue  Character  of 

Per  cent  residue 

. 0.14' 

. 0.24 

0.30  Particles  of  hard  clay 
0.64  and  sand 
. 0.25  ► 


Per  cent 
..  3.6 
. . 3.5 
. . 16.6 


Burning  test : — 


Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

02 

24 

White  

. . . 2.8' 

01 

24.3 

White  

. . . 3.3 

3 

22 

White  

...  4.2 

6 

21 

White  

...  4.3 

Earthy  fracture 

9 

17 

Cream  white  

. . . 5.0 

12 

12 

Cream  white  

...  6.4 

i 

Granular  fracture;  nu- 

13 

8 

Cream  white  

...  7.2 1 

1 

merous  flinty  parti- 

15 

6 

Buff;  lightly  bluestoned 

...  8.3 1 

\ 

cles  and  fine  iron 

i 

stain 

Fusion  test 

: — Deforms  between  cones  30  and  31. 

Summary 

The  bonding  strength  of  the  clay  is  low.  The  drying  shrinkage  is  medium  low. 
The  total  shrinkage  at  cone  9 is  medium.  It  has  a low  porosity  at  cone  15.  It  is 
a refractory  clay. 

Suggested  uses : Refractories. 


Sample  No.  134 

(Clay  pit  at  west  end  of  Goose  Lake  area) 

This  is  a clay  of  medium  hardness,  and  gray  colored  but  stained  with  yellow. 
Tempered  with  water,  it  has  a medium  degree  of  plasticity  and  shows  a tendency  to 


laminate  when  forced  through  a die. 

Water  of  plasticity per  cent  31.8 

Shrinkage  water  per  cent  18.5 

Pore  water per  cent  13.3 

Modulus  of  rupture lbs.  per  sq.  in.  442 

With  50%  standard  sand — Modulus  of  rupture  lbs.  per  sq.  in.  194 

Slaking  test,  average  min.  14 


144 


ILLINOIS  FIRE  CLAYS 


Screen  test : — 
Mesh 


20  

60  

80  

120  

200  

Drying  shrinkage 


Linear;  dry  length  7.6 

Linear;  wet  length  7.1 

Burning  test : — 


Residue 

Character  of 

Per  cent 

residue 

. 0.1 

Sand 

. 0.7 

Sand 

. 0.1 

Sand 

. 0.9 

Sand 

. 0.3 

Sand 

Per  cent 

Burning 

Cone 

Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04 

30 

Cream  white 

1.41 

02 

26 

Cream  white 

3.0 1 

2 

17 

Cream  white 

5-4  \ 

Earthy  fracture 

5 

15 

Cream  white 

6.0 

9 

11 

Cream  white 

6.7] 

13 

4.1 

Light  gray  

7.2 

Vitreous ; not  glassy 

14 

4.0 

6.4 

15 

4.3 

Light  brown  exterior ; 

bluestoned 

or  light  gray 

6.3 

Fusion  test : — Deforms  at  cone  28. 

Summary 

The  clay  has  a medium  high  strength  and  a medium  low  bonding  strength.  The 
drying  shrinkage  is  medium.  The  amount  of  screen  residues  is  low.  At  cone  9 the 
total  shrinkage  is  medium  high.  It  reaches  a low  degree  of  porosity  at  cone  13  and 
shows  no  sign  of  overburning  at  cone  15.  It  is  a refractory  clay. 

Suggested  uses : Refractories,  architectural  terra  cotta,  stoneware,  sanitary  ware, 
face  brick. 

Sample  No.  X 

(Anderson  farm  in  Goose  Lake  township) 

This  is  a drab  colored,  flinty  clay,  which  develops  a medium  plasticity  when  tem- 
pered with  water — i.  e.,  it  is  rather  sandy  or  grainy.  The  plastic  mass  laminates 
badly  when  squeezed  through  a die. 

Water  of  plasticity per  cent  26.6 

Shrinkage  water per  cent  14.6 

Pore  water  per  cent  12.0 

Modulus  of  rupture lbs.  per  sq.  in.  317.4 

With  50%  standard  sand — Modulus  of  rupture lbs.  per  sq.  in.  202.3 

Screen  test : — 

Mesh  Residue  Character  of 

Per  cent  residue 


10. 

14. 

20. 

35. 

48. 

65, 


2.9 

1.8 

2.8 

8.5 

5.5 
5.4 


Fragments  of  coal  and 
shale 


JOHNSON  COUNTY 


145 


100 3.9  'j  Fragments  of  coal  and 

150 2.7  j-  shale,  and  some  mica 

200 3.0  J 

Drying  shrinkage : — 

Per  cent 

Linear  6.2 

Volume  26 


Burning 

Cone 

test : — 

Porosity 

Color 

Hardness 

Total 

shrinkage 

Remarks 

04 

Per  cent 
10.0 

Gray 

Very  hard  . . . . 

Per  cent 
12 

Granular  fracture 

01 

6.9 

Gray 

Very  hard  . . . 

13 

1 

12.5 

Gray 

Very  hard  . . . , 

12 

3 

6.8 

Gray 

Very  hard  

12.7 

5 

2.4 

Gray 

Very  hard  . . . . 

12.9 

Slightly  bluestoned 

7 

1.3 

Gray 

Very  hard  

12.9 

9 

0.4 

Gray 

Very  hard  . . . . 

12.9 

12 

0.5 

Gray 

Very  hard  . . . . 

13.1 

14 

0.5 

Gray 

Very  hard  . . . . 

12.2 

Some  iron  specks 

Fusion  test: — It  deforms  at 

cone  28. 

Summary 

The  clay  has  a medium  strength  and  bonding  strength.  The  air  shrinkage  and 
total  shrinkage  are  medium.  It  is  almost  completely  vitrified  at  cone  5 and  shows 
no  signs  of  overburning  throughout  the  firing  range.  It  is  refractory. 

Suggested  uses : Refractories,  particularly  those  of  a close  texture. 


JOHNSON  COUNTY 

About  two  miles  southeast  of  Ozark  station  is  a deposit  of  Pottsville 
oil  shale  or  cannel  coal  which  has  been  investigated  by  the  Survey.  Perhaps 
the  best  typical  exposure  of  this  deposit  and  the  associated  strata  is  that  on 
the  Stone  land,  a section  of  which  is  here  given: 

Section  of  oil  shale  measured  in  a test  pit  on  the  Frank  Stone  land 
in  the  NW.  % NW.  yA  sec . 35,  T.  11  S.,  R.  4 E. 


Thickness 
Fi,  In. 

8.  Soil,  yellow  1 to  5 

7.  Shale,  chocolate,  siliceous 4 2 

6.  Mud,  red,  merely  a streak 

5.  Oil  shale  2 9 

4.  Coal,  bituminous  154 

3.  Coal,  cannel  4 

2.  Coal,  bituminous,  with  peacock-colored  blotches 2 

1.  “Fire  clay,”  white  5-4-  . . 


In  connection  with  the  sampling  of  the  oil  shale  a sample  of  the  under- 
lying clay  was  taken  and  tested  with  the  results  that  follow. 


146 


ILLINOIS  FIRE  CLAYS 


Sample  No.  C-18 — 1 


(Sample  taken  from  below  the  cannel  coal  near  Ozark  in  sec.  35,  T.  11  S.,  R.  4 E.) 

This  sample  is  medium  hard,  gray  colored  clay;  mottled  with  brown,  which  latter 
color  may  be  due  to  the  presence  of  organic  matter.  It  has  rather  poor  plasticity. 


Water  of  plasticity  . 

22.09 

Shrinkage  water  . . . 

9.20 

Pore  water 

12.89 

Modulus  of  rupture 

147.3 

Slaking  test,  average 

8 

Drying  shrinkage,  linear 

4.4 

Burning  test : — 

Total 

Cone  Porosity 

Color 

shrinkage 

Remarks 

Per  cent 

Per  cent 

04  18.7 

Light  tan  

8.3  ] 

01  16.4 

Light  tan  

7.3 

Earthy  fracture 

1 17.9 

Gray  

9 

5 9.4 

Dark  gray  

11.5 

7 3.1 

Dark  gray  

7 

Shows  signs  of 

over- 

burning 

Fusion  test: — It  fuses  at  cone  16. 

Summary 

The  clay  has  a medium  low  strength  and  a medium  drying  shrinkage.  The 
burning  shrinkage  at  cone  5 is  medium  high.  It  seems  to  be  overburned  at  cone  7. 
The  trial  pieces  have  the  appearance  of  having  been  subjected  to  reducing  conditions 
at  and  above  cone  5.  The  clay  is  non-refractory,  in  fact,  it  is  very  fusible. 
Suggested  uses  : Brick. 

Tabulation  of  Certain  Physical  Tests 

A knowledge  of  certain  of  the  physical  tests  of  a clay  will  enable  the 
experienced  person  to  determine  very  quickly  whether  it  is  likely  to  be  of 
value  for  a specific  purpose.  Accordingly  there  are  grouped  in  the  following 
paragraphs  classifications  of  the  clays  examined  according  to  the  results 
obtained  in  the  more  significant  tests.  A full  explanation  of  the  methods 
of  testing  and  the  interpretation  has  been  given  elsewhere. 

Slaking  test: — The  samples  which  required  more  than  thirty  minutes 
for  slaking  according  to  the  standard  test  were:  Nos.  22,  38,  44  (169)  55, 

58.  59,  60,  97,  98,  100,  129,  136. 

Fusion  test: — The  samples  which  fused  below  cone  27  were:  Nos.  17, 
37-a,  41,  42,  47,  50,  52,  54,  55,  56,  57,  58,  61,  62,  67,  69,  70,  73-a,  74,  75-a, 
75-b,  79,  80,  81,  82,  83,  84,  85,  86,  89,  91,  97,  102,  130-a,  131,  136. 

The  samples  which  fused  between  cones  27  and  32  inclusive  were : 
Nos.  9,  16,  22,  23,  25,  27,  28,  29,  30,  37,  38,  44,  45  (1678),  46,  48,  51,  53, 

59,  60,  65,  66,  71,  73-b,  73-c,  75,  77,  78,  87,  88,  90,  92,  93,  94,  95,  96,  98, 
99,  100,  101,  121,  122,  129,  133,  134,  X. 

The  samples  which  fused  at  cones  33  and  above  were:  Nos.  11,  18,  26. 


TABULATION  OF  PHYSICAL  TESTS 


147 


Porosities: — A grouping  of  the  samples  in  accordance  with  their  porosi- 
ties at  various  cones  is  given  in  the  following  table : 


5%  or  less  at  or 
below  cone  5 

5%  or  less  between 
cones  5 and  9 

5%  or  less  between 
cones  9 and  12 

5%  or  less  between 
cones  12  and  15 

10%  or  more  at 
cone  12  or  above 

23 

F 

G 

18 

16 

26 

25 

K3 

38 

46 

29 

27 

49 

54 

50 

30 

28 

51 

56 

70 

42 

37 

73-a 

65 

75-a 

55 

37-a 

75 

71 

79 

57 

52 

90 

74 

84 

58 

66 

96 

77 

89 

59 

81 

97 

87 

94 

60 

86 

92 

98* 

61 

121 

99 

62 

122 

134 

101 

67 

69 

73-b 

73-c 

82 

83 

85 

88 

93 

102 

131 

♦Probably. 


Strength  tests: — The  following  are  the  transverse  strength  tests  of  the 
various  clays  reported  in  terms  of  the  moduli  of  rupture  in  pounds  per  square 
inch.  The  symbol  “p”  is  used  to  indicate  results  obtained  in  testing  the  clay 
only.  The  symbol  “b”  indicates  the  test  of  a mixture  of  equal  parts  of 
standard  sand  and  clay;  that  is  to  say,  the  “bonding  strength.” 


Sample 

Below  200  lbs.  per  sq.  in. 

Between  200  and  400  lbs. 
per  sq.  in. 

Above  400  lbs.  per  sq.  in. 

i 

P 

b 

P 

b 

P 

b 

9 

104.4 

11 

43.4 

16 

64.1 

17 

180.9 

23 

311.2 

302.3 

25 

141.2 

131.2 

26 

137.5 

259 

27 

120.9 

265 

28 

192 

151.8 

29 

286.1 

30 

345 

229 

Sample 

37 

37-a 

38 

42 

44 

45 

46 

47 

49 

50 

51 

52 

53 

54 

55 

56 

57 

58 

59 

60 

61 

65 

66 

67 

69 

70 

71 

73-a 

73-b 

73-c 

74 

75 

75-a 

75-b 

77 

78 

79 

80 

82 

83 

84 

85 

86 

87 

88 

89 


ILLINOIS  FIRE  CLAYS 


Below  200  lbs.  per  sq.  in. 

Between  200  and  400  lbs. 
per  sq.  in. 

Above  400  lbs. 

. per  sq.  in. 

P 

b 

P 

b 

P 

b 

249.7 

487.2 

240.7 

238.7 

164.8 

283.1 

325.6 

465.6 

299.5 

526.6 

217.4 

214 

365  8 

189.5 

369  2 

207 

275.5 

199 

446.8 

380.2 

243.9 

120.2 

103.1 

250 

250 

172.5 

145.1 

231.8 

462 

370 

565.5 

165.7 

124.6 

169.8 

589 

164.5 

427 

372.7 

567 

240.8 

414.5 



303.8 

248.7 



242 

498.3 

302.8 

609 



144 

328 

352.2 

356.5 

339.3 

221.8 

214.9 

295.6 



192 

269.6 

' 

199.6 

263 



320 

261 

325.8 

209.4 



119.5 

287.3 

445.4 

185.2 

484.8 

329 

664 

214 

386.7 

190.2 

290.3 

497.6 

243 

179 

137.6 

TABULATION  OF  PHYSICAL  TESTS 


149 


Sample 

Below  200  lbs.  per  sq.  in 

Between  200  and  400  lbs. 
per  sq.  in. 

Above  400  lbs.  per  sq.  in. 

P 

b 

P 

b 

P 

b 

90 

290 

420 

91 

309.5 

236.7 

92 

201 

93 

94 

302.5 

554.7 

140.6 

96 

107.3 

277 

97 

201 

565 

98 

149 

246 

99 

107 

215 

100 

222 

475 

101 

177 

532 

102 

297 

223 

121 

191 

123.3 

122 

177 

136.5 

129 

247 

795 

131 

192.6 

361.8 

133 

59.6 

134 

194 

442 

SUMMARY 

Grouping  of  Clays  According  to  Uses 
In  the  following  summary  the  clays  have  been  grouped  according  to  uses 
to  which  they  seem  to  be  adapted.  It  is  to  be  understood  that  the  arrange- 
ment is  based  solely  upon  the  data  given,  and  not  upon  special  tests. 
Refractory  clays  burning  to  a porosity  of  5 per  cent  or  less  at  cone  temperatures  not 
exceeding  cone  9: 

Samples  F,  G,  K3,  Nos.  23,  25,  26,  27,  28,  29,  30,  37,  37a,  55,  59,  66,  73c,  88,  93, 

121,  122. 

Refractory  clays  which  have  a porosity  of  more  than  5 per  cent  below  cone  9: 

Nos.  16,  18,  22,38,  44,45,  46,  49,  51,  53,  54,  56,  71,  75,  77,  78,  80,  87,  90,  92,  94,  96,  97, 
98,  99,  100,  101,  129,  133,  134. 

Stoneware  clays: 

Nos.  9,  23,  25,  26,  28,  29,  30,  37,  37a,  38,  41,  42,  44,  47,  49,  51,  52,  54,  56,  57,  65,  66, 
70,  71,  73a,  73c,  74,  75,  75b,  77,  78,  79,  80,  85,  87,  88,  89,  90,  91,  92,  93,  96,  97,  100, 
101,  121.  122,  134. 

Architectural  terra  cotta  clays: 

Nos.  9,  23,  25,  26,  28,  29,  30,  37,  37a,  38,  41,  42,  44,  47,  49,  51,  52,  53  54,  55,  56,  57, 
58,  60,  65,  66,  70,  71,  73a,  73c,  74,  75,  75b,  77,  78,  79,  80,  84,  85,  87,  88,  89,  90,  91,  92, 
93,  96,  97,  100,  101,  121,  122,  134. 

Sewer  pipe  clays: 

Nos.  50,  57,  59,  60,  65,  67,  73b,  83,  86. 

Face  brick  clays: 

Nos.  42,  45,  47,  49,  50,  51,  52,  53,  54,  56,  57,  58,  59,  61,  62,  65,  67,  70,  71,  73a,  73b, 
73c,  74.  75b,  77,  78,  79,  80,  83,  84,  85,  86,  87,  88,  89,  91,  92,  93,  96,  97,  98,  99,  100, 

101,  134. 

Common  brick , tile,  etc.: 

Nos.  61,  62,  69,  75a,  81,  82,  86,  102,  131,  136. 

Sanitary  ware  clays: 

Nos.  23,  25,  26,  28,  29,  30,  37,  37a,  38,  41,  42,  44,  47,  49,  51,  52,  53,  54,  55,  56,  57, 
65,  66,  70,  71,  73a,  73c,  74,  75b,  77,  78,  79,  80,  85,  87,  88,  89,  90,  91,  92,  93,  96,  97, 
98,  99,  100,  101,  134. 


